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Diffstat (limited to '')
| -rw-r--r-- | layout/generic/nsIFrame.h | 5606 |
1 files changed, 5606 insertions, 0 deletions
diff --git a/layout/generic/nsIFrame.h b/layout/generic/nsIFrame.h new file mode 100644 index 0000000000..03eea383b1 --- /dev/null +++ b/layout/generic/nsIFrame.h @@ -0,0 +1,5606 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* interface for all rendering objects */ + +#ifndef nsIFrame_h___ +#define nsIFrame_h___ + +#ifndef MOZILLA_INTERNAL_API +#error This header/class should only be used within Mozilla code. It should not be used by extensions. +#endif + +#if (defined(XP_WIN) && !defined(HAVE_64BIT_BUILD)) || defined(ANDROID) +// Blink's magic depth limit from its HTML parser (513) plus as much as fits in +// the default run-time stack on armv7 Android on Dalvik when using display: +// block minus a bit just to be sure. The Dalvik default stack crashes at 588. +// ART can do a few frames more. Using the same number for 32-bit Windows for +// consistency. Over there, Blink's magic depth of 513 doesn't fit in the +// default stack of 1 MB, but this magic depth fits when the default is grown by +// mere 192 KB (tested in 64 KB increments). +// +// 32-bit Windows has a different limit compared to 64-bit desktop, because the +// default stack size affects all threads and consumes address space. Fixing +// that is bug 1257522. +// +// 32-bit Android on ARM already happens to have defaults that are close enough +// to what makes sense as a temporary measure on Windows, so adjusting the +// Android stack can be a follow-up. The stack on 64-bit ARM needs adjusting in +// any case before 64-bit ARM can become tier-1. See bug 1400811. +// +// Ideally, we'd get rid of this smaller limit and make 32-bit Windows and +// Android capable of working with the Linux/Mac/Win64 number below. +# define MAX_REFLOW_DEPTH 585 +#else +// Blink's magic depth limit from its HTML parser times two. Also just about +// fits within the system default runtime stack limit of 8 MB on 64-bit Mac and +// Linux with display: table-cell. +# define MAX_REFLOW_DEPTH 1026 +#endif + +/* nsIFrame is in the process of being deCOMtaminated, i.e., this file is + eventually going to be eliminated, and all callers will use nsFrame instead. + At the moment we're midway through this process, so you will see inlined + functions and member variables in this file. -dwh */ + +#include <algorithm> +#include <stdio.h> + +#include "CaretAssociationHint.h" +#include "FrameProperties.h" +#include "LayoutConstants.h" +#include "mozilla/AspectRatio.h" +#include "mozilla/Attributes.h" +#include "mozilla/Baseline.h" +#include "mozilla/EnumSet.h" +#include "mozilla/EventForwards.h" +#include "mozilla/Maybe.h" +#include "mozilla/RelativeTo.h" +#include "mozilla/Result.h" +#include "mozilla/SmallPointerArray.h" +#include "mozilla/ToString.h" +#include "mozilla/WritingModes.h" +#include "nsDirection.h" +#include "nsFrameList.h" +#include "nsFrameState.h" +#include "mozilla/ReflowInput.h" +#include "nsIContent.h" +#include "nsITheme.h" +#include "nsQueryFrame.h" +#include "mozilla/ComputedStyle.h" +#include "nsStyleStruct.h" +#include "Visibility.h" +#include "nsChangeHint.h" +#include "mozilla/EnumSet.h" +#include "mozilla/gfx/2D.h" +#include "mozilla/gfx/CompositorHitTestInfo.h" +#include "mozilla/gfx/MatrixFwd.h" +#include "mozilla/intl/BidiEmbeddingLevel.h" +#include "nsDisplayItemTypes.h" +#include "nsPresContext.h" +#include "nsTHashSet.h" + +#ifdef ACCESSIBILITY +# include "mozilla/a11y/AccTypes.h" +#endif + +/** + * New rules of reflow: + * 1. you get a WillReflow() followed by a Reflow() followed by a DidReflow() in + * order (no separate pass over the tree) + * 2. it's the parent frame's responsibility to size/position the child's view + * (not the child frame's responsibility as it is today) during reflow (and + * before sending the DidReflow() notification) + * 3. positioning of child frames (and their views) is done on the way down the + * tree, and sizing of child frames (and their views) on the way back up + * 4. if you move a frame (outside of the reflow process, or after reflowing + * it), then you must make sure that its view (or its child frame's views) + * are re-positioned as well. It's reasonable to not position the view until + * after all reflowing the entire line, for example, but the frame should + * still be positioned and sized (and the view sized) during the reflow + * (i.e., before sending the DidReflow() notification) + * 5. the view system handles moving of widgets, i.e., it's not our problem + */ + +class nsAtom; +class nsView; +class nsFrameSelection; +class nsIWidget; +class nsIScrollableFrame; +class nsISelectionController; +class nsILineIterator; +class gfxSkipChars; +class gfxSkipCharsIterator; +class gfxContext; +class nsLineList_iterator; +class nsAbsoluteContainingBlock; +class nsContainerFrame; +class nsPlaceholderFrame; +class nsStyleChangeList; +class nsViewManager; +class nsWindowSizes; + +struct CharacterDataChangeInfo; + +namespace mozilla { + +enum class PeekOffsetOption : uint8_t; +enum class PseudoStyleType : uint8_t; +enum class TableSelectionMode : uint32_t; + +class nsDisplayItem; +class nsDisplayList; +class nsDisplayListBuilder; +class nsDisplayListSet; + +class ServoRestyleState; +class EffectSet; +class LazyLogModule; +class PresShell; +class WidgetGUIEvent; +class WidgetMouseEvent; + +struct PeekOffsetStruct; + +namespace layers { +class Layer; +class LayerManager; +} // namespace layers + +namespace layout { +class ScrollAnchorContainer; +} // namespace layout + +} // namespace mozilla + +//---------------------------------------------------------------------- + +// 1 million CSS pixels less than our max app unit measure. +// For reflowing with an "infinite" available inline space per [css-sizing]. +// (reflowing with an NS_UNCONSTRAINEDSIZE available inline size isn't allowed +// and leads to assertions) +#define INFINITE_ISIZE_COORD nscoord(NS_MAXSIZE - (1000000 * 60)) + +//---------------------------------------------------------------------- + +namespace mozilla { + +enum class LayoutFrameType : uint8_t { +#define FRAME_TYPE(ty_, ...) ty_, +#include "mozilla/FrameTypeList.h" +#undef FRAME_TYPE +}; + +} // namespace mozilla + +enum nsSelectionAmount { + eSelectCharacter = 0, // a single Unicode character; + // do not use this (prefer Cluster) unless you + // are really sure it's what you want + eSelectCluster = 1, // a grapheme cluster: this is usually the right + // choice for movement or selection by "character" + // as perceived by the user + eSelectWord = 2, + eSelectWordNoSpace = 3, // select a "word" without selecting the following + // space, no matter what the default platform + // behavior is + eSelectLine = 4, // previous drawn line in flow. + // NOTE that selection code depends on the ordering of the above values, + // allowing simple <= tests to check categories of caret movement. + // Don't rearrange without checking the usage in nsSelection.cpp! + + eSelectBeginLine = 5, + eSelectEndLine = 6, + eSelectNoAmount = 7, // just bounce back current offset. + eSelectParagraph = 8 // select a "paragraph" +}; + +//---------------------------------------------------------------------- +// Reflow status returned by the Reflow() methods. +class nsReflowStatus final { + public: + nsReflowStatus() + : mFloatClearType(mozilla::StyleClear::None), + mInlineBreak(InlineBreak::None), + mCompletion(Completion::FullyComplete), + mNextInFlowNeedsReflow(false), + mFirstLetterComplete(false) {} + + // Reset all the member variables. + void Reset() { + mFloatClearType = mozilla::StyleClear::None; + mInlineBreak = InlineBreak::None; + mCompletion = Completion::FullyComplete; + mNextInFlowNeedsReflow = false; + mFirstLetterComplete = false; + } + + // Return true if all member variables have their default values. + bool IsEmpty() const { + return (IsFullyComplete() && !IsInlineBreak() && !mNextInFlowNeedsReflow && + !mFirstLetterComplete); + } + + // There are three possible completion statuses, represented by + // mCompletion. + // + // Incomplete means the frame does *not* map all its content, and the + // parent frame should create a continuing frame. + // + // OverflowIncomplete means that the frame has an overflow that is not + // complete, but its own box is complete. (This happens when the content + // overflows a fixed-height box.) The reflower should place and size the + // frame and continue its reflow, but it needs to create an overflow + // container as a continuation for this frame. See "Overflow containers" + // documentation in nsContainerFrame.h for more information. + // + // FullyComplete means the frame is neither Incomplete nor + // OverflowIncomplete. This is the default state for a nsReflowStatus. + // + enum class Completion : uint8_t { + // The order of the enum values is important, which represents the + // precedence when merging. + FullyComplete, + OverflowIncomplete, + Incomplete, + }; + + bool IsIncomplete() const { return mCompletion == Completion::Incomplete; } + bool IsOverflowIncomplete() const { + return mCompletion == Completion::OverflowIncomplete; + } + bool IsFullyComplete() const { + return mCompletion == Completion::FullyComplete; + } + // Just for convenience; not a distinct state. + bool IsComplete() const { return !IsIncomplete(); } + + void SetIncomplete() { mCompletion = Completion::Incomplete; } + void SetOverflowIncomplete() { mCompletion = Completion::OverflowIncomplete; } + + // mNextInFlowNeedsReflow bit flag means that the next-in-flow is dirty, + // and also needs to be reflowed. This status only makes sense for a frame + // that is not complete, i.e. you wouldn't set mNextInFlowNeedsReflow when + // IsComplete() is true. + bool NextInFlowNeedsReflow() const { return mNextInFlowNeedsReflow; } + void SetNextInFlowNeedsReflow() { mNextInFlowNeedsReflow = true; } + + // Merge the frame completion status bits from aStatus into this. + void MergeCompletionStatusFrom(const nsReflowStatus& aStatus) { + if (mCompletion < aStatus.mCompletion) { + mCompletion = aStatus.mCompletion; + } + + // These asserts ensure that the mCompletion merging works as we expect. + // (Incomplete beats OverflowIncomplete, which beats FullyComplete.) + static_assert( + Completion::Incomplete > Completion::OverflowIncomplete && + Completion::OverflowIncomplete > Completion::FullyComplete, + "mCompletion merging won't work without this!"); + + mNextInFlowNeedsReflow |= aStatus.mNextInFlowNeedsReflow; + } + + // There are three possible inline-break statuses, represented by + // mInlineBreak. + // + // "None" means no break is requested. + // "Before" means the break should occur before the frame. + // "After" means the break should occur after the frame. + // (Here, "the frame" is the frame whose reflow results are being reported by + // this nsReflowStatus.) + // + enum class InlineBreak : uint8_t { + None, + Before, + After, + }; + + bool IsInlineBreak() const { return mInlineBreak != InlineBreak::None; } + bool IsInlineBreakBefore() const { + return mInlineBreak == InlineBreak::Before; + } + bool IsInlineBreakAfter() const { return mInlineBreak == InlineBreak::After; } + mozilla::StyleClear FloatClearType() const { return mFloatClearType; } + + // Set the inline line-break-before status, and reset other bit flags. Note + // that other frame completion status isn't expected to matter after calling + // this method. + // + // Here's one scenario where a child frame would report this status. Suppose + // the child has "break-inside:avoid" in its style, and the child (and its + // content) won't fit in the available block-size. This child would want to + // report this status so that it gets pushed (in its entirety) to the next + // column/page where it will hopefully fit. + void SetInlineLineBreakBeforeAndReset() { + Reset(); + mFloatClearType = mozilla::StyleClear::None; + mInlineBreak = InlineBreak::Before; + } + + // Set the inline line-break-after status. The clear type can be changed + // via the optional aClearType param. + void SetInlineLineBreakAfter( + mozilla::StyleClear aClearType = mozilla::StyleClear::None) { + mFloatClearType = aClearType; + mInlineBreak = InlineBreak::After; + } + + // mFirstLetterComplete bit flag means the break was induced by + // completion of a first-letter. + bool FirstLetterComplete() const { return mFirstLetterComplete; } + void SetFirstLetterComplete() { mFirstLetterComplete = true; } + + private: + mozilla::StyleClear mFloatClearType; + InlineBreak mInlineBreak; + Completion mCompletion; + bool mNextInFlowNeedsReflow : 1; + bool mFirstLetterComplete : 1; +}; + +// Convert nsReflowStatus to a human-readable string. +std::ostream& operator<<(std::ostream& aStream, const nsReflowStatus& aStatus); + +namespace mozilla { + +// Loosely: https://drafts.csswg.org/css-align-3/#shared-alignment-context +enum class AlignmentContext { + Inline, + Table, + Flexbox, + Grid, +}; + +/* + * For replaced elements only. Gets the intrinsic dimensions of this element, + * which can be specified on a per-axis basis. + */ +struct IntrinsicSize { + Maybe<nscoord> width; + Maybe<nscoord> height; + + IntrinsicSize() = default; + + IntrinsicSize(nscoord aWidth, nscoord aHeight) + : width(Some(aWidth)), height(Some(aHeight)) {} + + explicit IntrinsicSize(const nsSize& aSize) + : IntrinsicSize(aSize.Width(), aSize.Height()) {} + + Maybe<nsSize> ToSize() const { + return width && height ? Some(nsSize(*width, *height)) : Nothing(); + } + + bool operator==(const IntrinsicSize& rhs) const { + return width == rhs.width && height == rhs.height; + } + bool operator!=(const IntrinsicSize& rhs) const { return !(*this == rhs); } +}; + +// Pseudo bidi embedding level indicating nonexistence. +static const mozilla::intl::BidiEmbeddingLevel kBidiLevelNone = + mozilla::intl::BidiEmbeddingLevel(0xff); + +struct FrameBidiData { + mozilla::intl::BidiEmbeddingLevel baseLevel; + mozilla::intl::BidiEmbeddingLevel embeddingLevel; + // The embedding level of virtual bidi formatting character before + // this frame if any. kBidiLevelNone is used to indicate nonexistence + // or unnecessity of such virtual character. + mozilla::intl::BidiEmbeddingLevel precedingControl; +}; + +} // namespace mozilla + +/// Generic destructor for frame properties. Calls delete. +template <typename T> +static void DeleteValue(T* aPropertyValue) { + delete aPropertyValue; +} + +/// Generic destructor for frame properties. Calls Release(). +template <typename T> +static void ReleaseValue(T* aPropertyValue) { + aPropertyValue->Release(); +} + +//---------------------------------------------------------------------- + +/** + * nsIFrame logging constants. We redefine the nspr + * PRLogModuleInfo.level field to be a bitfield. Each bit controls a + * specific type of logging. Each logging operation has associated + * inline methods defined below. + * + * Due to the redefinition of the level field we cannot use MOZ_LOG directly + * as that will cause assertions due to invalid log levels. + */ +#define NS_FRAME_TRACE_CALLS 0x1 +#define NS_FRAME_TRACE_PUSH_PULL 0x2 +#define NS_FRAME_TRACE_CHILD_REFLOW 0x4 +#define NS_FRAME_TRACE_NEW_FRAMES 0x8 + +#define NS_FRAME_LOG_TEST(_lm, _bit) \ + (int(((mozilla::LogModule*)(_lm))->Level()) & (_bit)) + +#ifdef DEBUG +# define NS_FRAME_LOG(_bit, _args) \ + PR_BEGIN_MACRO \ + if (NS_FRAME_LOG_TEST(nsIFrame::sFrameLogModule, _bit)) { \ + printf_stderr _args; \ + } \ + PR_END_MACRO +#else +# define NS_FRAME_LOG(_bit, _args) +#endif + +// XXX Need to rework this so that logging is free when it's off +#ifdef DEBUG +# define NS_FRAME_TRACE_IN(_method) Trace(_method, true) + +# define NS_FRAME_TRACE_OUT(_method) Trace(_method, false) + +# define NS_FRAME_TRACE(_bit, _args) \ + PR_BEGIN_MACRO \ + if (NS_FRAME_LOG_TEST(nsIFrame::sFrameLogModule, _bit)) { \ + TraceMsg _args; \ + } \ + PR_END_MACRO + +# define NS_FRAME_TRACE_REFLOW_IN(_method) Trace(_method, true) + +# define NS_FRAME_TRACE_REFLOW_OUT(_method, _status) \ + Trace(_method, false, _status) + +#else +# define NS_FRAME_TRACE(_bits, _args) +# define NS_FRAME_TRACE_IN(_method) +# define NS_FRAME_TRACE_OUT(_method) +# define NS_FRAME_TRACE_REFLOW_IN(_method) +# define NS_FRAME_TRACE_REFLOW_OUT(_method, _status) +#endif + +//---------------------------------------------------------------------- + +// Frame allocation boilerplate macros. Every subclass of nsFrame must +// either use NS_{DECL,IMPL}_FRAMEARENA_HELPERS pair for allocating +// memory correctly, or use NS_DECL_ABSTRACT_FRAME to declare a frame +// class abstract and stop it from being instantiated. If a frame class +// without its own operator new and GetFrameId gets instantiated, the +// per-frame recycler lists in nsPresArena will not work correctly, +// with potentially catastrophic consequences (not enough memory is +// allocated for a frame object). + +#define NS_DECL_FRAMEARENA_HELPERS(class) \ + NS_DECL_QUERYFRAME_TARGET(class) \ + static constexpr nsIFrame::ClassID kClassID = nsIFrame::ClassID::class##_id; \ + void* operator new(size_t, mozilla::PresShell*) MOZ_MUST_OVERRIDE; \ + nsQueryFrame::FrameIID GetFrameId() const override MOZ_MUST_OVERRIDE { \ + return nsQueryFrame::class##_id; \ + } + +#define NS_IMPL_FRAMEARENA_HELPERS(class) \ + void* class ::operator new(size_t sz, mozilla::PresShell* aShell) { \ + return aShell->AllocateFrame(nsQueryFrame::class##_id, sz); \ + } + +#define NS_DECL_ABSTRACT_FRAME(class) \ + void* operator new(size_t, mozilla::PresShell*) MOZ_MUST_OVERRIDE = delete; \ + nsQueryFrame::FrameIID GetFrameId() const override MOZ_MUST_OVERRIDE = 0; + +//---------------------------------------------------------------------- + +namespace mozilla { + +// A simple class to group stuff that we need to keep around when tearing down +// a frame tree. +// +// Native anonymous content created by the frames need to get unbound _after_ +// the frame has been destroyed, see bug 1400618. +// +// We destroy the anonymous content bottom-up (so, in reverse order), because +// it's a bit simpler, though we generally don't have that much nested anonymous +// content (except for scrollbars). +struct MOZ_RAII FrameDestroyContext { + explicit FrameDestroyContext(PresShell* aPs) : mPresShell(aPs) {} + + void AddAnonymousContent(already_AddRefed<nsIContent>&& aContent) { + if (RefPtr<nsIContent> content = aContent) { + mAnonymousContent.AppendElement(std::move(content)); + } + } + + ~FrameDestroyContext(); + + private: + PresShell* const mPresShell; + AutoTArray<RefPtr<nsIContent>, 100> mAnonymousContent; +}; + +} // namespace mozilla + +/** + * A frame in the layout model. This interface is supported by all frame + * objects. + * + * Frames can have multiple child lists: the default child list + * (referred to as the <i>principal</i> child list, and additional named + * child lists. There is an ordering of frames within a child list, but + * there is no order defined between frames in different child lists of + * the same parent frame. + * + * Frames are NOT reference counted. Use the Destroy() member function + * to destroy a frame. The lifetime of the frame hierarchy is bounded by the + * lifetime of the presentation shell which owns the frames. + * + * nsIFrame is a private Gecko interface. If you are not Gecko then you + * should not use it. If you're not in layout, then you won't be able to + * link to many of the functions defined here. Too bad. + * + * If you're not in layout but you must call functions in here, at least + * restrict yourself to calling virtual methods, which won't hurt you as badly. + */ +class nsIFrame : public nsQueryFrame { + public: + using AlignmentContext = mozilla::AlignmentContext; + using BaselineSharingGroup = mozilla::BaselineSharingGroup; + using BaselineExportContext = mozilla::BaselineExportContext; + template <typename T> + using Maybe = mozilla::Maybe<T>; + template <typename T, typename E> + using Result = mozilla::Result<T, E>; + using Nothing = mozilla::Nothing; + using OnNonvisible = mozilla::OnNonvisible; + using ReflowInput = mozilla::ReflowInput; + using ReflowOutput = mozilla::ReflowOutput; + using Visibility = mozilla::Visibility; + using LengthPercentage = mozilla::LengthPercentage; + using ContentRelevancy = mozilla::ContentRelevancy; + + using nsDisplayItem = mozilla::nsDisplayItem; + using nsDisplayList = mozilla::nsDisplayList; + using nsDisplayListSet = mozilla::nsDisplayListSet; + using nsDisplayListBuilder = mozilla::nsDisplayListBuilder; + + typedef mozilla::ComputedStyle ComputedStyle; + typedef mozilla::FrameProperties FrameProperties; + typedef mozilla::layers::LayerManager LayerManager; + typedef mozilla::gfx::DrawTarget DrawTarget; + typedef mozilla::gfx::Matrix Matrix; + typedef mozilla::gfx::Matrix4x4 Matrix4x4; + typedef mozilla::gfx::Matrix4x4Flagged Matrix4x4Flagged; + typedef mozilla::Sides Sides; + typedef mozilla::LogicalSides LogicalSides; + typedef mozilla::SmallPointerArray<nsDisplayItem> DisplayItemArray; + + typedef nsQueryFrame::ClassID ClassID; + + protected: + using ChildList = mozilla::FrameChildList; + using ChildListID = mozilla::FrameChildListID; + using ChildListIDs = mozilla::FrameChildListIDs; + + public: + // nsQueryFrame + NS_DECL_QUERYFRAME + NS_DECL_QUERYFRAME_TARGET(nsIFrame) + + explicit nsIFrame(ComputedStyle* aStyle, nsPresContext* aPresContext, + ClassID aID) + : mRect(), + mContent(nullptr), + mComputedStyle(aStyle), + mPresContext(aPresContext), + mParent(nullptr), + mNextSibling(nullptr), + mPrevSibling(nullptr), + mState(NS_FRAME_FIRST_REFLOW | NS_FRAME_IS_DIRTY), + mWritingMode(aStyle), + mClass(aID), + mMayHaveRoundedCorners(false), + mHasImageRequest(false), + mHasFirstLetterChild(false), + mParentIsWrapperAnonBox(false), + mIsWrapperBoxNeedingRestyle(false), + mReflowRequestedForCharDataChange(false), + mForceDescendIntoIfVisible(false), + mBuiltDisplayList(false), + mFrameIsModified(false), + mHasModifiedDescendants(false), + mHasOverrideDirtyRegion(false), + mMayHaveWillChangeBudget(false), +#ifdef DEBUG + mWasVisitedByAutoFrameConstructionPageName(false), +#endif + mIsPrimaryFrame(false), + mMayHaveTransformAnimation(false), + mMayHaveOpacityAnimation(false), + mAllDescendantsAreInvisible(false), + mHasBSizeChange(false), + mHasPaddingChange(false), + mInScrollAnchorChain(false), + mHasColumnSpanSiblings(false), + mDescendantMayDependOnItsStaticPosition(false), + mShouldGenerateComputedInfo(false) { + MOZ_ASSERT(mComputedStyle); + MOZ_ASSERT(mPresContext); + mozilla::PodZero(&mOverflow); + MOZ_COUNT_CTOR(nsIFrame); + } + explicit nsIFrame(ComputedStyle* aStyle, nsPresContext* aPresContext) + : nsIFrame(aStyle, aPresContext, ClassID::nsIFrame_id) {} + + nsPresContext* PresContext() const { return mPresContext; } + + mozilla::PresShell* PresShell() const { return PresContext()->PresShell(); } + + virtual nsQueryFrame::FrameIID GetFrameId() const MOZ_MUST_OVERRIDE { + return kFrameIID; + } + + /** + * Called to initialize the frame. This is called immediately after creating + * the frame. + * + * If the frame is a continuing frame, then aPrevInFlow indicates the previous + * frame (the frame that was split). + * + * Each subclass that need a view should override this method and call + * CreateView() after calling its base class Init(). + * + * @param aContent the content object associated with the frame + * @param aParent the parent frame + * @param aPrevInFlow the prev-in-flow frame + */ + virtual void Init(nsIContent* aContent, nsContainerFrame* aParent, + nsIFrame* aPrevInFlow); + + void* operator new(size_t, mozilla::PresShell*) MOZ_MUST_OVERRIDE; + + using DestroyContext = mozilla::FrameDestroyContext; + + /** + * Flags for PeekOffsetCharacter, PeekOffsetNoAmount, PeekOffsetWord return + * values. + */ + enum FrameSearchResult { + // Peek found a appropriate offset within frame. + FOUND = 0x00, + // try next frame for offset. + CONTINUE = 0x1, + // offset not found because the frame was empty of text. + CONTINUE_EMPTY = 0x2 | CONTINUE, + // offset not found because the frame didn't contain any text that could be + // selected. + CONTINUE_UNSELECTABLE = 0x4 | CONTINUE, + }; + + /** + * Options for PeekOffsetCharacter(). + */ + struct MOZ_STACK_CLASS PeekOffsetCharacterOptions { + // Whether to restrict result to valid cursor locations (between grapheme + // clusters) - if this is included, maintains "normal" behavior, otherwise, + // used for selection by "code unit" (instead of "character") + bool mRespectClusters; + // Whether to check user-select style value - if this is included, checks + // if user-select is all, then, it may return CONTINUE_UNSELECTABLE. + bool mIgnoreUserStyleAll; + + PeekOffsetCharacterOptions() + : mRespectClusters(true), mIgnoreUserStyleAll(false) {} + }; + + virtual void Destroy(DestroyContext&); + + protected: + /** + * Return true if the frame is part of a Selection. + * Helper method to implement the public IsSelected() API. + */ + virtual bool IsFrameSelected() const; + + template <class Source> + friend class do_QueryFrameHelper; // to read mClass + friend class nsBlockFrame; // for GetCaretBaseline + friend class nsContainerFrame; // for ReparentFrameViewTo + + virtual ~nsIFrame(); + + // Overridden to prevent the global delete from being called, since + // the memory came out of an arena instead of the heap. + // + // Ideally this would be private and undefined, like the normal + // operator new. Unfortunately, the C++ standard requires an + // overridden operator delete to be accessible to any subclass that + // defines a virtual destructor, so we can only make it protected; + // worse, some C++ compilers will synthesize calls to this function + // from the "deleting destructors" that they emit in case of + // delete-expressions, so it can't even be undefined. + void operator delete(void* aPtr, size_t sz); + + private: + // Left undefined; nsFrame objects are never allocated from the heap. + void* operator new(size_t sz) noexcept(true); + + // Returns true if this frame has any kind of CSS animations. + bool HasCSSAnimations(); + + // Returns true if this frame has any kind of CSS transitions. + bool HasCSSTransitions(); + + public: + /** + * Get the content object associated with this frame. Does not add a + * reference. + */ + nsIContent* GetContent() const { return mContent; } + + /** + * @brief Get the closest native anonymous subtree root if the content is in a + * native anonymous subtree. + * + * @return The root of native anonymous subtree which the content belongs to. + * Otherwise, nullptr. + */ + nsIContent* GetClosestNativeAnonymousSubtreeRoot() const { + return mContent ? mContent->GetClosestNativeAnonymousSubtreeRoot() + : nullptr; + } + + /** + * Get the frame that should be the parent for the frames of child elements + * May return nullptr during reflow + */ + virtual nsContainerFrame* GetContentInsertionFrame() { return nullptr; } + + /** + * Move any frames on our overflow list to the end of our principal list. + * @return true if there were any overflow frames + */ + virtual bool DrainSelfOverflowList() { return false; } + + /** + * Get the frame that should be scrolled if the content associated + * with this frame is targeted for scrolling. For frames implementing + * nsIScrollableFrame this will return the frame itself. For frames + * like nsTextControlFrame that contain a scrollframe, will return + * that scrollframe. + */ + virtual nsIScrollableFrame* GetScrollTargetFrame() const { return nullptr; } + + /** + * Get the offsets of the frame. most will be 0,0 + * + */ + virtual std::pair<int32_t, int32_t> GetOffsets() const; + + /** + * Reset the offsets when splitting frames during Bidi reordering + * + */ + virtual void AdjustOffsetsForBidi(int32_t aStart, int32_t aEnd) {} + + /** + * Get the style associated with this frame. + */ + ComputedStyle* Style() const { return mComputedStyle; } + + void AssertNewStyleIsSane(ComputedStyle&) +#ifdef MOZ_DIAGNOSTIC_ASSERT_ENABLED + ; +#else + { + } +#endif + + void SetComputedStyle(ComputedStyle* aStyle) { + if (aStyle != mComputedStyle) { + AssertNewStyleIsSane(*aStyle); + RefPtr<ComputedStyle> oldComputedStyle = std::move(mComputedStyle); + mComputedStyle = aStyle; + DidSetComputedStyle(oldComputedStyle); + } + } + + /** + * SetComputedStyleWithoutNotification is for changes to the style + * context that should suppress style change processing, in other + * words, those that aren't really changes. This generally means only + * changes that happen during frame construction. + */ + void SetComputedStyleWithoutNotification(ComputedStyle* aStyle) { + if (aStyle != mComputedStyle) { + mComputedStyle = aStyle; + } + } + + protected: + // Style post processing hook + // Attention: the old style is the one we're forgetting, + // and hence possibly completely bogus for GetStyle* purposes. + // Use PeekStyleData instead. + virtual void DidSetComputedStyle(ComputedStyle* aOldComputedStyle); + + public: +/** + * Define typesafe getter functions for each style struct by + * preprocessing the list of style structs. These functions are the + * preferred way to get style data. The macro creates functions like: + * const nsStyleBorder* StyleBorder(); + * const nsStyleColor* StyleColor(); + * + * Callers outside of libxul should use nsIDOMWindow::GetComputedStyle() + * instead of these accessors. + * + * Callers can use Style*WithOptionalParam if they're in a function that + * accepts an *optional* pointer the style struct. + */ +#define STYLE_STRUCT(name_) \ + const nsStyle##name_* Style##name_() const MOZ_NONNULL_RETURN { \ + NS_ASSERTION(mComputedStyle, "No style found!"); \ + return mComputedStyle->Style##name_(); \ + } \ + const nsStyle##name_* Style##name_##WithOptionalParam( \ + const nsStyle##name_* aStyleStruct) const MOZ_NONNULL_RETURN { \ + if (aStyleStruct) { \ + MOZ_ASSERT(aStyleStruct == Style##name_()); \ + return aStyleStruct; \ + } \ + return Style##name_(); \ + } +#include "nsStyleStructList.h" +#undef STYLE_STRUCT + + /** Also forward GetVisitedDependentColor to the style */ + template <typename T, typename S> + nscolor GetVisitedDependentColor(T S::*aField) { + return mComputedStyle->GetVisitedDependentColor(aField); + } + + /** + * These methods are to access any additional ComputedStyles that + * the frame may be holding. + * + * These are styles that are children of the frame's primary style and are NOT + * used as styles for any child frames. + * + * These contexts also MUST NOT have any child styles whatsoever. If you need + * to insert styles into the style tree, then you should create pseudo element + * frames to own them. + * + * The indicies must be consecutive and implementations MUST return null if + * asked for an index that is out of range. + */ + virtual ComputedStyle* GetAdditionalComputedStyle(int32_t aIndex) const; + + virtual void SetAdditionalComputedStyle(int32_t aIndex, + ComputedStyle* aComputedStyle); + + /** + * @param aSelectionStatus nsISelectionController::getDisplaySelection. + */ + already_AddRefed<ComputedStyle> ComputeSelectionStyle( + int16_t aSelectionStatus) const; + + already_AddRefed<ComputedStyle> ComputeHighlightSelectionStyle( + const nsAtom* aHighlightName); + + /** + * Accessor functions for geometric parent. + */ + nsContainerFrame* GetParent() const { return mParent; } + + bool CanBeDynamicReflowRoot() const; + + /** + * Gets the parent of a frame, using the parent of the placeholder for + * out-of-flow frames. + */ + inline nsContainerFrame* GetInFlowParent() const; + + /** + * Gets the primary frame of the closest flattened tree ancestor that has a + * frame (flattened tree ancestors may not have frames in presence of display: + * contents). + */ + inline nsIFrame* GetClosestFlattenedTreeAncestorPrimaryFrame() const; + + /** + * Return the placeholder for this frame (which must be out-of-flow). + * @note this will only return non-null if |this| is the first-in-flow + * although we don't assert that here for legacy reasons. + */ + inline nsPlaceholderFrame* GetPlaceholderFrame() const { + MOZ_ASSERT(HasAnyStateBits(NS_FRAME_OUT_OF_FLOW)); + return GetProperty(PlaceholderFrameProperty()); + } + + /** + * Set this frame's parent to aParent. + * If the frame may have moved into or out of a scrollframe's + * frame subtree, + * StickyScrollContainer::NotifyReparentedFrameAcrossScrollFrameBoundary must + * also be called. + */ + void SetParent(nsContainerFrame* aParent); + + /** + * The frame's writing-mode, used for logical layout computations. + * It's usually the 'writing-mode' computed value, but there are exceptions: + * * inner table frames copy the value from the table frame + * (@see nsTableRowGroupFrame::Init, nsTableRowFrame::Init etc) + * * the root element frame propagates its value to its ancestors. + * The value may obtain from the principal <body> element. + * (@see nsCSSFrameConstructor::ConstructDocElementFrame) + * * the internal anonymous frames of the root element copy their value + * from the parent. + * (@see nsIFrame::Init) + * * a scrolled frame propagates its value to its ancestor scroll frame + * (@see nsHTMLScrollFrame::ReloadChildFrames) + */ + mozilla::WritingMode GetWritingMode() const { return mWritingMode; } + + /** + * Construct a writing mode for line layout in this frame. This is + * the writing mode of this frame, except that if this frame is styled with + * unicode-bidi:plaintext, we reset the direction to the resolved paragraph + * level of the given subframe (typically the first frame on the line), + * because the container frame could be split by hard line breaks into + * multiple paragraphs with different base direction. + * @param aSelfWM the WM of 'this' + */ + mozilla::WritingMode WritingModeForLine(mozilla::WritingMode aSelfWM, + nsIFrame* aSubFrame) const; + + /** + * Bounding rect of the frame. + * + * For frames that are laid out according to CSS box model rules the values + * are in app units, and the origin is relative to the upper-left of the + * geometric parent. The size includes the content area, borders, and + * padding. + * + * Frames that are laid out according to SVG's coordinate space based rules + * (frames with the NS_FRAME_SVG_LAYOUT bit set, which *excludes* + * SVGOuterSVGFrame) are different. Many frames of this type do not set or + * use mRect, in which case the frame rect is undefined. The exceptions are: + * + * - SVGInnerSVGFrame + * - SVGGeometryFrame (used for <path>, <circle>, etc.) + * - SVGImageFrame + * - SVGForeignObjectFrame + * + * For these frames the frame rect contains the frame's element's userspace + * bounds including fill, stroke and markers, but converted to app units + * rather than being in user units (CSS px). In the SVG code "userspace" is + * defined to be the coordinate system for the attributes that define an + * element's geometry (such as the 'cx' attribute for <circle>). For more + * precise details see these frames' implementations of the ReflowSVG method + * where mRect is set. + * + * Note: moving or sizing the frame does not affect the view's size or + * position. + */ + nsRect GetRect() const { return mRect; } + nsPoint GetPosition() const { return mRect.TopLeft(); } + nsSize GetSize() const { return mRect.Size(); } + nsRect GetRectRelativeToSelf() const { + return nsRect(nsPoint(0, 0), mRect.Size()); + } + + /** + * Like the frame's rect (see |GetRect|), which is the border rect, + * other rectangles of the frame, in app units, relative to the parent. + */ + nsRect GetPaddingRect() const; + nsRect GetPaddingRectRelativeToSelf() const; + nsRect GetContentRect() const; + nsRect GetContentRectRelativeToSelf() const; + nsRect GetMarginRect() const; + nsRect GetMarginRectRelativeToSelf() const; + + /** + * Dimensions and position in logical coordinates in the frame's writing mode + * or another writing mode + */ + mozilla::LogicalRect GetLogicalRect(const nsSize& aContainerSize) const { + return GetLogicalRect(GetWritingMode(), aContainerSize); + } + mozilla::LogicalPoint GetLogicalPosition(const nsSize& aContainerSize) const { + return GetLogicalPosition(GetWritingMode(), aContainerSize); + } + mozilla::LogicalSize GetLogicalSize() const { + return GetLogicalSize(GetWritingMode()); + } + mozilla::LogicalRect GetLogicalRect(mozilla::WritingMode aWritingMode, + const nsSize& aContainerSize) const { + return mozilla::LogicalRect(aWritingMode, GetRect(), aContainerSize); + } + mozilla::LogicalPoint GetLogicalPosition(mozilla::WritingMode aWritingMode, + const nsSize& aContainerSize) const { + return GetLogicalRect(aWritingMode, aContainerSize).Origin(aWritingMode); + } + mozilla::LogicalSize GetLogicalSize(mozilla::WritingMode aWritingMode) const { + return mozilla::LogicalSize(aWritingMode, GetSize()); + } + nscoord IStart(const nsSize& aContainerSize) const { + return IStart(GetWritingMode(), aContainerSize); + } + nscoord IStart(mozilla::WritingMode aWritingMode, + const nsSize& aContainerSize) const { + return GetLogicalPosition(aWritingMode, aContainerSize).I(aWritingMode); + } + nscoord BStart(const nsSize& aContainerSize) const { + return BStart(GetWritingMode(), aContainerSize); + } + nscoord BStart(mozilla::WritingMode aWritingMode, + const nsSize& aContainerSize) const { + return GetLogicalPosition(aWritingMode, aContainerSize).B(aWritingMode); + } + nscoord ISize() const { return ISize(GetWritingMode()); } + nscoord ISize(mozilla::WritingMode aWritingMode) const { + return GetLogicalSize(aWritingMode).ISize(aWritingMode); + } + nscoord BSize() const { return BSize(GetWritingMode()); } + nscoord BSize(mozilla::WritingMode aWritingMode) const { + return GetLogicalSize(aWritingMode).BSize(aWritingMode); + } + mozilla::LogicalSize ContentSize() const { + return ContentSize(GetWritingMode()); + } + mozilla::LogicalSize ContentSize(mozilla::WritingMode aWritingMode) const { + mozilla::WritingMode wm = GetWritingMode(); + const auto bp = GetLogicalUsedBorderAndPadding(wm) + .ApplySkipSides(GetLogicalSkipSides()) + .ConvertTo(aWritingMode, wm); + const auto size = GetLogicalSize(aWritingMode); + return mozilla::LogicalSize( + aWritingMode, + std::max(0, size.ISize(aWritingMode) - bp.IStartEnd(aWritingMode)), + std::max(0, size.BSize(aWritingMode) - bp.BStartEnd(aWritingMode))); + } + + /** + * When we change the size of the frame's border-box rect, we may need to + * reset the overflow rect if it was previously stored as deltas. + * (If it is currently a "large" overflow and could be re-packed as deltas, + * we don't bother as the cost of the allocation has already been paid.) + * @param aRebuildDisplayItems If true, then adds this frame to the + * list of modified frames for display list building if the rect has changed. + * Only pass false if you're sure that the relevant display items will be + * rebuilt already (possibly by an ancestor being in the modified list), or if + * this is a temporary change. + */ + void SetRect(const nsRect& aRect, bool aRebuildDisplayItems = true) { + if (aRect == mRect) { + return; + } + if (mOverflow.mType != OverflowStorageType::Large && + mOverflow.mType != OverflowStorageType::None) { + mozilla::OverflowAreas overflow = GetOverflowAreas(); + mRect = aRect; + SetOverflowAreas(overflow); + } else { + mRect = aRect; + } + if (aRebuildDisplayItems) { + MarkNeedsDisplayItemRebuild(); + } + } + /** + * Set this frame's rect from a logical rect in its own writing direction + */ + void SetRect(const mozilla::LogicalRect& aRect, + const nsSize& aContainerSize) { + SetRect(GetWritingMode(), aRect, aContainerSize); + } + /** + * Set this frame's rect from a logical rect in a different writing direction + * (GetPhysicalRect will assert if the writing mode doesn't match) + */ + void SetRect(mozilla::WritingMode aWritingMode, + const mozilla::LogicalRect& aRect, + const nsSize& aContainerSize) { + SetRect(aRect.GetPhysicalRect(aWritingMode, aContainerSize)); + } + + /** + * Set this frame's size from a logical size in its own writing direction. + * This leaves the frame's logical position unchanged, which means its + * physical position may change (for right-to-left modes). + */ + void SetSize(const mozilla::LogicalSize& aSize) { + SetSize(GetWritingMode(), aSize); + } + /* + * Set this frame's size from a logical size in a different writing direction. + * This leaves the frame's logical position in the given mode unchanged, + * which means its physical position may change (for right-to-left modes). + */ + void SetSize(mozilla::WritingMode aWritingMode, + const mozilla::LogicalSize& aSize) { + if (aWritingMode.IsPhysicalRTL()) { + nscoord oldWidth = mRect.Width(); + SetSize(aSize.GetPhysicalSize(aWritingMode)); + mRect.x -= mRect.Width() - oldWidth; + } else { + SetSize(aSize.GetPhysicalSize(aWritingMode)); + } + } + + /** + * Set this frame's physical size. This leaves the frame's physical position + * (topLeft) unchanged. + * @param aRebuildDisplayItems If true, then adds this frame to the + * list of modified frames for display list building if the size has changed. + * Only pass false if you're sure that the relevant display items will be + * rebuilt already (possibly by an ancestor being in the modified list), or if + * this is a temporary change. + */ + void SetSize(const nsSize& aSize, bool aRebuildDisplayItems = true) { + SetRect(nsRect(mRect.TopLeft(), aSize), aRebuildDisplayItems); + } + + void SetPosition(const nsPoint& aPt); + void SetPosition(mozilla::WritingMode aWritingMode, + const mozilla::LogicalPoint& aPt, + const nsSize& aContainerSize) { + // We subtract mRect.Size() from the container size to account for + // the fact that logical origins in RTL coordinate systems are at + // the top right of the frame instead of the top left. + SetPosition( + aPt.GetPhysicalPoint(aWritingMode, aContainerSize - mRect.Size())); + } + + /** + * Move the frame, accounting for relative positioning. Use this when + * adjusting the frame's position by a known amount, to properly update its + * saved normal position (see GetNormalPosition below). + * + * This must be used only when moving a frame *after* + * ReflowInput::ApplyRelativePositioning is called. When moving + * a frame during the reflow process prior to calling + * ReflowInput::ApplyRelativePositioning, the position should + * simply be adjusted directly (e.g., using SetPosition()). + */ + void MovePositionBy(const nsPoint& aTranslation); + + /** + * As above, using a logical-point delta in a given writing mode. + */ + void MovePositionBy(mozilla::WritingMode aWritingMode, + const mozilla::LogicalPoint& aTranslation) { + // The LogicalPoint represents a vector rather than a point within a + // rectangular coordinate space, so we use a null containerSize when + // converting logical to physical. + const nsSize nullContainerSize; + MovePositionBy( + aTranslation.GetPhysicalPoint(aWritingMode, nullContainerSize)); + } + + /** + * Return frame's rect without relative positioning + */ + nsRect GetNormalRect() const; + mozilla::LogicalRect GetLogicalNormalRect( + mozilla::WritingMode aWritingMode, const nsSize& aContainerSize) const { + return mozilla::LogicalRect(aWritingMode, GetNormalRect(), aContainerSize); + } + + /** + * Returns frame's rect as required by the GetBoundingClientRect() DOM API. + */ + nsRect GetBoundingClientRect(); + + /** + * Return frame's position without relative positioning. + * If aHasProperty is provided, returns whether the normal position + * was stored in a frame property. + */ + inline nsPoint GetNormalPosition(bool* aHasProperty = nullptr) const; + inline mozilla::LogicalPoint GetLogicalNormalPosition( + mozilla::WritingMode aWritingMode, const nsSize& aContainerSize) const; + + virtual nsPoint GetPositionOfChildIgnoringScrolling(const nsIFrame* aChild) { + return aChild->GetPosition(); + } + + nsPoint GetPositionIgnoringScrolling() const; + +#define NS_DECLARE_FRAME_PROPERTY_WITH_DTOR(prop, type, dtor) \ + static const mozilla::FramePropertyDescriptor<type>* prop() { \ + /* Use of constexpr caused startup crashes with MSVC2015u1 PGO. */ \ + static const auto descriptor = \ + mozilla::FramePropertyDescriptor<type>::NewWithDestructor<dtor>(); \ + return &descriptor; \ + } + +// Don't use this unless you really know what you're doing! +#define NS_DECLARE_FRAME_PROPERTY_WITH_FRAME_IN_DTOR(prop, type, dtor) \ + static const mozilla::FramePropertyDescriptor<type>* prop() { \ + /* Use of constexpr caused startup crashes with MSVC2015u1 PGO. */ \ + static const auto descriptor = mozilla::FramePropertyDescriptor< \ + type>::NewWithDestructorWithFrame<dtor>(); \ + return &descriptor; \ + } + +#define NS_DECLARE_FRAME_PROPERTY_WITHOUT_DTOR(prop, type) \ + static const mozilla::FramePropertyDescriptor<type>* prop() { \ + /* Use of constexpr caused startup crashes with MSVC2015u1 PGO. */ \ + static const auto descriptor = \ + mozilla::FramePropertyDescriptor<type>::NewWithoutDestructor(); \ + return &descriptor; \ + } + +#define NS_DECLARE_FRAME_PROPERTY_DELETABLE(prop, type) \ + NS_DECLARE_FRAME_PROPERTY_WITH_DTOR(prop, type, DeleteValue) + +#define NS_DECLARE_FRAME_PROPERTY_RELEASABLE(prop, type) \ + NS_DECLARE_FRAME_PROPERTY_WITH_DTOR(prop, type, ReleaseValue) + +#define NS_DECLARE_FRAME_PROPERTY_WITH_DTOR_NEVER_CALLED(prop, type) \ + static void AssertOnDestroyingProperty##prop(type*) { \ + MOZ_ASSERT_UNREACHABLE( \ + "Frame property " #prop \ + " should never be destroyed by the FrameProperties class"); \ + } \ + NS_DECLARE_FRAME_PROPERTY_WITH_DTOR(prop, type, \ + AssertOnDestroyingProperty##prop) + +#define NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(prop, type) \ + NS_DECLARE_FRAME_PROPERTY_WITHOUT_DTOR(prop, mozilla::SmallValueHolder<type>) + + NS_DECLARE_FRAME_PROPERTY_WITHOUT_DTOR(IBSplitSibling, nsContainerFrame) + NS_DECLARE_FRAME_PROPERTY_WITHOUT_DTOR(IBSplitPrevSibling, nsContainerFrame) + + NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(NormalPositionProperty, nsPoint) + NS_DECLARE_FRAME_PROPERTY_DELETABLE(ComputedOffsetProperty, nsMargin) + + NS_DECLARE_FRAME_PROPERTY_DELETABLE(OutlineInnerRectProperty, nsRect) + NS_DECLARE_FRAME_PROPERTY_DELETABLE(PreEffectsBBoxProperty, nsRect) + NS_DECLARE_FRAME_PROPERTY_DELETABLE(PreTransformOverflowAreasProperty, + mozilla::OverflowAreas) + + NS_DECLARE_FRAME_PROPERTY_DELETABLE(OverflowAreasProperty, + mozilla::OverflowAreas) + + // The initial overflow area passed to FinishAndStoreOverflow. This is only + // set on frames that Preserve3D() or HasPerspective() or IsTransformed(), and + // when at least one of the overflow areas differs from the frame bound rect. + NS_DECLARE_FRAME_PROPERTY_DELETABLE(InitialOverflowProperty, + mozilla::OverflowAreas) + +#ifdef DEBUG + // InitialOverflowPropertyDebug is added to the frame to indicate that either + // the InitialOverflowProperty has been stored or the InitialOverflowProperty + // has been suppressed due to being set to the default value (frame bounds) + NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(DebugInitialOverflowPropertyApplied, + bool) +#endif + + NS_DECLARE_FRAME_PROPERTY_DELETABLE(UsedMarginProperty, nsMargin) + NS_DECLARE_FRAME_PROPERTY_DELETABLE(UsedPaddingProperty, nsMargin) + NS_DECLARE_FRAME_PROPERTY_DELETABLE(UsedBorderProperty, nsMargin) + + // This tracks the start and end page value for a frame. + // + // https://www.w3.org/TR/css-page-3/#using-named-pages + // + // This is only tracked during paginated frame construction. + // This is used to implement fragmentation based on CSS page names. During + // frame construction, we insert page breaks when we begin a new page box and + // the previous page box had a different name. + struct PageValues { + // A value of null indicates that the value is equal to what auto resolves + // to for this frame. + RefPtr<const nsAtom> mStartPageValue = nullptr; + RefPtr<const nsAtom> mEndPageValue = nullptr; + }; + NS_DECLARE_FRAME_PROPERTY_DELETABLE(PageValuesProperty, PageValues) + + const nsAtom* GetStartPageValue() const { + if (const PageValues* const values = GetProperty(PageValuesProperty())) { + return values->mStartPageValue; + } + return nullptr; + } + + const nsAtom* GetEndPageValue() const { + if (const PageValues* const values = GetProperty(PageValuesProperty())) { + return values->mEndPageValue; + } + return nullptr; + } + + private: + // The value that the CSS page-name "auto" keyword resolves to for children + // of this frame. + // + // A missing value for this property indicates that the auto value is the + // empty string, which is the default if no ancestors of a frame specify a + // page name. This avoids ever storing this property if the document doesn't + // use named pages. + // + // https://www.w3.org/TR/css-page-3/#using-named-pages + // + // Ideally this would be a const atom, but that isn't possible with the + // Release() call. This isn't too bad, since it's hidden behind constness- + // preserving getter/setter. + NS_DECLARE_FRAME_PROPERTY_RELEASABLE(AutoPageValueProperty, nsAtom) + + public: + // Get the value that the CSS page-name "auto" keyword resolves to for + // children of this frame. + // This is needed when propagating page-name values up the frame tree. + const nsAtom* GetAutoPageValue() const { + if (const nsAtom* const atom = GetProperty(AutoPageValueProperty())) { + return atom; + } + return nsGkAtoms::_empty; + } + void SetAutoPageValue(const nsAtom* aAtom) { + MOZ_ASSERT(aAtom, "Atom must not be null"); + nsAtom* const atom = const_cast<nsAtom*>(aAtom); + if (atom != nsGkAtoms::_empty) { + SetProperty(AutoPageValueProperty(), do_AddRef(atom).take()); + } + } + + NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(LineBaselineOffset, nscoord) + + NS_DECLARE_FRAME_PROPERTY_DELETABLE(InvalidationRect, nsRect) + + NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(RefusedAsyncAnimationProperty, bool) + + NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(FragStretchBSizeProperty, nscoord) + + // The block-axis margin-box size associated with eBClampMarginBoxMinSize. + NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(BClampMarginBoxMinSizeProperty, nscoord) + + NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(IBaselinePadProperty, nscoord) + NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(BBaselinePadProperty, nscoord) + + NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(BidiDataProperty, + mozilla::FrameBidiData) + + NS_DECLARE_FRAME_PROPERTY_WITHOUT_DTOR(PlaceholderFrameProperty, + nsPlaceholderFrame) + + NS_DECLARE_FRAME_PROPERTY_RELEASABLE(OffsetPathCache, mozilla::gfx::Path) + + mozilla::FrameBidiData GetBidiData() const { + bool exists; + mozilla::FrameBidiData bidiData = GetProperty(BidiDataProperty(), &exists); + if (!exists) { + bidiData.precedingControl = mozilla::kBidiLevelNone; + } + return bidiData; + } + + mozilla::intl::BidiEmbeddingLevel GetBaseLevel() const { + return GetBidiData().baseLevel; + } + + mozilla::intl::BidiEmbeddingLevel GetEmbeddingLevel() const { + return GetBidiData().embeddingLevel; + } + + /** + * Return the distance between the border edge of the frame and the + * margin edge of the frame. Like GetRect(), returns the dimensions + * as of the most recent reflow. + * + * This doesn't include any margin collapsing that may have occurred. + * It also doesn't consider GetSkipSides()/GetLogicalSkipSides(), so + * may report nonzero values on sides that are actually skipped for + * this fragment. + * + * It also treats 'auto' margins as zero, and treats any margins that + * should have been turned into 'auto' because of overconstraint as + * having their original values. + */ + virtual nsMargin GetUsedMargin() const; + virtual mozilla::LogicalMargin GetLogicalUsedMargin( + mozilla::WritingMode aWritingMode) const { + return mozilla::LogicalMargin(aWritingMode, GetUsedMargin()); + } + + /** + * Return the distance between the border edge of the frame (which is + * its rect) and the padding edge of the frame. Like GetRect(), returns + * the dimensions as of the most recent reflow. + * + * This doesn't consider GetSkipSides()/GetLogicalSkipSides(), so + * may report nonzero values on sides that are actually skipped for + * this fragment. + * + * Note that this differs from StyleBorder()->GetComputedBorder() in + * that this describes a region of the frame's box, and + * StyleBorder()->GetComputedBorder() describes a border. They differ + * for tables (particularly border-collapse tables) and themed + * elements. + */ + virtual nsMargin GetUsedBorder() const; + virtual mozilla::LogicalMargin GetLogicalUsedBorder( + mozilla::WritingMode aWritingMode) const { + return mozilla::LogicalMargin(aWritingMode, GetUsedBorder()); + } + + /** + * Return the distance between the padding edge of the frame and the + * content edge of the frame. Like GetRect(), returns the dimensions + * as of the most recent reflow. + * + * This doesn't consider GetSkipSides()/GetLogicalSkipSides(), so + * may report nonzero values on sides that are actually skipped for + * this fragment. + */ + virtual nsMargin GetUsedPadding() const; + virtual mozilla::LogicalMargin GetLogicalUsedPadding( + mozilla::WritingMode aWritingMode) const { + return mozilla::LogicalMargin(aWritingMode, GetUsedPadding()); + } + + nsMargin GetUsedBorderAndPadding() const { + return GetUsedBorder() + GetUsedPadding(); + } + mozilla::LogicalMargin GetLogicalUsedBorderAndPadding( + mozilla::WritingMode aWritingMode) const { + return mozilla::LogicalMargin(aWritingMode, GetUsedBorderAndPadding()); + } + + /** + * The area to paint box-shadows around. The default is the border rect. + * (nsFieldSetFrame overrides this). + */ + virtual nsRect VisualBorderRectRelativeToSelf() const { + return nsRect(0, 0, mRect.Width(), mRect.Height()); + } + + /** + * Get the size, in app units, of the border radii. It returns FALSE iff all + * returned radii == 0 (so no border radii), TRUE otherwise. + * For the aRadii indexes, use the enum HalfCorner constants in gfx/2d/Types.h + * If a side is skipped via aSkipSides, its corners are forced to 0. + * + * All corner radii are then adjusted so they do not require more + * space than aBorderArea, according to the algorithm in css3-background. + * + * aFrameSize is used as the basis for percentage widths and heights. + * aBorderArea is used for the adjustment of radii that might be too + * large. + * + * Return whether any radii are nonzero. + */ + static bool ComputeBorderRadii(const mozilla::BorderRadius&, + const nsSize& aFrameSize, + const nsSize& aBorderArea, Sides aSkipSides, + nscoord aRadii[8]); + + /* + * Given a set of border radii for one box (e.g., border box), convert + * it to the equivalent set of radii for another box (e.g., in to + * padding box, out to outline box) by reducing radii or increasing + * nonzero radii as appropriate. + * + * Indices into aRadii are the enum HalfCorner constants in gfx/2d/Types.h + * + * Note that insetting the radii is lossy, since it can turn nonzero radii + * into zero, and re-adjusting does not inflate zero radii. + * + * Therefore, callers should always adjust directly from the original value + * coming from style. + */ + static void AdjustBorderRadii(nscoord aRadii[8], const nsMargin& aOffsets); + + /** + * Fill in border radii for this frame. Return whether any are nonzero. + * Indices into aRadii are the enum HalfCorner constants in gfx/2d/Types.h + * aSkipSides is a union of SideBits::eLeft/Right/Top/Bottom bits that says + * which side(s) to skip. + * + * Note: GetMarginBoxBorderRadii() and GetShapeBoxBorderRadii() work only + * on frames that establish block formatting contexts since they don't + * participate in margin-collapsing. + */ + virtual bool GetBorderRadii(const nsSize& aFrameSize, + const nsSize& aBorderArea, Sides aSkipSides, + nscoord aRadii[8]) const; + bool GetBorderRadii(nscoord aRadii[8]) const; + bool GetMarginBoxBorderRadii(nscoord aRadii[8]) const; + bool GetPaddingBoxBorderRadii(nscoord aRadii[8]) const; + bool GetContentBoxBorderRadii(nscoord aRadii[8]) const; + bool GetBoxBorderRadii(nscoord aRadii[8], const nsMargin& aOffset) const; + bool GetShapeBoxBorderRadii(nscoord aRadii[8]) const; + + /** + * `GetNaturalBaselineBOffset`, but determines the baseline sharing group + * through `GetDefaultBaselineSharingGroup` (If not specified), assuming line + * layout context, and never fails, returning a synthesized baseline through + * `SynthesizeFallbackBaseline`. Unlike `GetNaturalBaselineBOffset`, Result is + * always relative to the block start of the frame. + */ + nscoord GetLogicalBaseline(mozilla::WritingMode aWM) const; + /** + * Same as the above, but with baseline sharing group & export + * context specified. + */ + nscoord GetLogicalBaseline(mozilla::WritingMode aWM, + BaselineSharingGroup aBaselineGroup, + BaselineExportContext aExportContext) const; + + /** + * Return true if the frame has a first(last) inline-axis baseline per + * CSS Box Alignment. If so, the returned baseline is the distance from + * the relevant block-axis border-box edge (Start for + * BaselineSharingGroup::First, end for BaselineSharingGroup::Last), where + * a positive value points towards the content-box. + * Some frames can export different baselines depending if it's in a line + * layout context or any other context (e.g. Flex, grid). + * https://drafts.csswg.org/css-align-3/#baseline-export + * @note The returned value is only valid when reflow is not needed. + * @note You should only call this on frames with a WM that's parallel to aWM. + * @note We're approaching `nsLayoutUtils::Get(First|Last)LineBaseline` == + * `GetNaturalBaselineBOffset(aWM, (First|Last), Other)`. Grid relies on + * baseline synthesis behaviour in `nsLayoutUtils` implementations (bug + * 1609403), which blocks its removal. + * @param aWM the writing-mode of the alignment context. + * @return the baseline offset, if one exists + */ + virtual Maybe<nscoord> GetNaturalBaselineBOffset( + mozilla::WritingMode aWM, BaselineSharingGroup aBaselineGroup, + BaselineExportContext aExportContext) const { + return Nothing{}; + } + + struct CaretBlockAxisMetrics { + nscoord mOffset = 0; + nscoord mExtent = 0; + }; + /** + * Get the offset (Block start of the caret) and extent of the caret in this + * frame. The returned offset is corrected for vertical & line-inverted + * writing modes. + */ + CaretBlockAxisMetrics GetCaretBlockAxisMetrics(mozilla::WritingMode, + const nsFontMetrics&) const; + // Gets the page-name value to be used for the page that contains this frame + // during paginated reflow. + const nsAtom* ComputePageValue() const MOZ_NONNULL_RETURN; + + /////////////////////////////////////////////////////////////////////////////// + // The public visibility API. + /////////////////////////////////////////////////////////////////////////////// + + /// @return true if we're tracking visibility for this frame. + bool TrackingVisibility() const { + return HasAnyStateBits(NS_FRAME_VISIBILITY_IS_TRACKED); + } + + /// @return the visibility state of this frame. See the Visibility enum + /// for the possible return values and their meanings. + Visibility GetVisibility() const; + + /// Update the visibility state of this frame synchronously. + /// XXX(seth): Avoid using this method; we should be relying on the refresh + /// driver for visibility updates. This method, which replaces + /// nsLayoutUtils::UpdateApproximateFrameVisibility(), exists purely as a + /// temporary measure to avoid changing behavior during the transition from + /// the old image visibility code. + void UpdateVisibilitySynchronously(); + + // A frame property which stores the visibility state of this frame. Right + // now that consists of an approximate visibility counter represented as a + // uint32_t. When the visibility of this frame is not being tracked, this + // property is absent. + NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(VisibilityStateProperty, uint32_t); + + protected: + /** + * Get the position of the baseline on which the caret needs to be placed, + * relative to the top of the frame. This is mostly needed for frames + * which return a baseline from GetBaseline which is not useful for + * caret positioning. + */ + virtual nscoord GetCaretBaseline() const { + return GetLogicalBaseline(GetWritingMode()); + } + + /** + * Subclasses can call this method to enable visibility tracking for this + * frame. + * + * If visibility tracking was previously disabled, this will schedule an + * update an asynchronous update of visibility. + */ + void EnableVisibilityTracking(); + + /** + * Subclasses can call this method to disable visibility tracking for this + * frame. + * + * Note that if visibility tracking was previously enabled, disabling + * visibility tracking will cause a synchronous call to OnVisibilityChange(). + */ + void DisableVisibilityTracking(); + + /** + * Called when a frame transitions between visibility states (for example, + * from nonvisible to visible, or from visible to nonvisible). + * + * @param aNewVisibility The new visibility state. + * @param aNonvisibleAction A requested action if the frame has become + * nonvisible. If Nothing(), no action is + * requested. If DISCARD_IMAGES is specified, the + * frame is requested to ask any images it's + * associated with to discard their surfaces if + * possible. + * + * Subclasses which override this method should call their parent class's + * implementation. + */ + virtual void OnVisibilityChange( + Visibility aNewVisibility, + const Maybe<OnNonvisible>& aNonvisibleAction = Nothing()); + + /** + * Synthesize a baseline for this element. The returned baseline is the + * distance from the relevant block-axis border-box edge (Start for + * BaselineSharingGroup::First, end for BaselineSharingGroup::Last), where a + * positive value points towards the content-box. + * @note This always returns a synthesized baseline, even if the element may + * have an actual baseline. + */ + virtual nscoord SynthesizeFallbackBaseline( + mozilla::WritingMode aWM, BaselineSharingGroup aBaselineGroup) const; + + public: + /** + * Get the suitable baseline sharing group for this element, assuming line + * layout. + */ + virtual BaselineSharingGroup GetDefaultBaselineSharingGroup() const { + return BaselineSharingGroup::First; + } + + /////////////////////////////////////////////////////////////////////////////// + // Internal implementation for the approximate frame visibility API. + /////////////////////////////////////////////////////////////////////////////// + + /** + * We track the approximate visibility of frames using a counter; if it's + * non-zero, then the frame is considered visible. Using a counter allows us + * to account for situations where the frame may be visible in more than one + * place (for example, via -moz-element), and it simplifies the + * implementation of our approximate visibility tracking algorithms. + * + * @param aNonvisibleAction A requested action if the frame has become + * nonvisible. If Nothing(), no action is + * requested. If DISCARD_IMAGES is specified, the + * frame is requested to ask any images it's + * associated with to discard their surfaces if + * possible. + */ + void DecApproximateVisibleCount( + const Maybe<OnNonvisible>& aNonvisibleAction = Nothing()); + void IncApproximateVisibleCount(); + + /** + * Get the specified child list. + * + * @param aListID identifies the requested child list. + * @return the child list. If the requested list is unsupported by this + * frame type, an empty list will be returned. + */ + virtual const nsFrameList& GetChildList(ChildListID aListID) const; + const nsFrameList& PrincipalChildList() const { + return GetChildList(mozilla::FrameChildListID::Principal); + } + + /** + * Sub-classes should override this methods if they want to append their own + * child lists into aLists. + */ + virtual void GetChildLists(nsTArray<ChildList>* aLists) const; + + /** + * Returns the child lists for this frame. + */ + AutoTArray<ChildList, 4> ChildLists() const { + AutoTArray<ChildList, 4> childLists; + GetChildLists(&childLists); + return childLists; + } + + /** + * Returns the child lists for this frame, including ones belong to a child + * document. + */ + AutoTArray<ChildList, 4> CrossDocChildLists(); + + /** + * Child frames are linked together in a doubly-linked list + */ + nsIFrame* GetNextSibling() const { return mNextSibling; } + void SetNextSibling(nsIFrame* aNextSibling) { + NS_ASSERTION(this != aNextSibling, + "Creating a circular frame list, this is very bad."); + if (mNextSibling && mNextSibling->GetPrevSibling() == this) { + mNextSibling->mPrevSibling = nullptr; + } + mNextSibling = aNextSibling; + if (mNextSibling) { + mNextSibling->mPrevSibling = this; + } + } + + nsIFrame* GetPrevSibling() const { return mPrevSibling; } + + /** + * Builds the display lists for the content represented by this frame + * and its descendants. The background+borders of this element must + * be added first, before any other content. + * + * This should only be called by methods in nsFrame. Instead of calling this + * directly, call either BuildDisplayListForStackingContext or + * BuildDisplayListForChild. + * + * See nsDisplayList.h for more information about display lists. + */ + virtual void BuildDisplayList(nsDisplayListBuilder* aBuilder, + const nsDisplayListSet& aLists) {} + /** + * Displays the caret onto the given display list builder. The caret is + * painted on top of the rest of the display list items. + */ + void DisplayCaret(nsDisplayListBuilder* aBuilder, nsDisplayList* aList); + + /** + * Get the preferred caret color at the offset. + * + * @param aOffset is offset of the content. + */ + virtual nscolor GetCaretColorAt(int32_t aOffset); + + bool IsThemed(nsITheme::Transparency* aTransparencyState = nullptr) const { + return IsThemed(StyleDisplay(), aTransparencyState); + } + bool IsThemed(const nsStyleDisplay* aDisp, + nsITheme::Transparency* aTransparencyState = nullptr) const { + if (!aDisp->HasAppearance()) { + return false; + } + nsIFrame* mutable_this = const_cast<nsIFrame*>(this); + nsPresContext* pc = PresContext(); + nsITheme* theme = pc->Theme(); + if (!theme->ThemeSupportsWidget(pc, mutable_this, + aDisp->EffectiveAppearance())) { + return false; + } + if (aTransparencyState) { + *aTransparencyState = theme->GetWidgetTransparency( + mutable_this, aDisp->EffectiveAppearance()); + } + return true; + } + + /** + * Builds a display list for the content represented by this frame, + * treating this frame as the root of a stacking context. + * Optionally sets aCreatedContainerItem to true if we created a + * single container display item for the stacking context, and no + * other wrapping items are needed. + */ + void BuildDisplayListForStackingContext( + nsDisplayListBuilder* aBuilder, nsDisplayList* aList, + bool* aCreatedContainerItem = nullptr); + + enum class DisplayChildFlag { + ForcePseudoStackingContext, + ForceStackingContext, + Inline, + }; + using DisplayChildFlags = mozilla::EnumSet<DisplayChildFlag>; + + /** + * Adjusts aDirtyRect for the child's offset, checks that the dirty rect + * actually intersects the child (or its descendants), calls BuildDisplayList + * on the child if necessary, and puts things in the right lists if the child + * is positioned. + * + * @param aFlags a set of of DisplayChildFlag values that are applicable for + * this operation. + */ + void BuildDisplayListForChild(nsDisplayListBuilder* aBuilder, + nsIFrame* aChild, + const nsDisplayListSet& aLists, + DisplayChildFlags aFlags = {}); + + void BuildDisplayListForSimpleChild(nsDisplayListBuilder* aBuilder, + nsIFrame* aChild, + const nsDisplayListSet& aLists); + + /** + * Helper for BuildDisplayListForChild, to implement this special-case for + * grid (and flex) items from the spec: + * The painting order of grid items is exactly the same as inline blocks, + * except that [...], and 'z-index' values other than 'auto' create a + * stacking context even if 'position' is 'static' (behaving exactly as if + * 'position' were 'relative'). https://drafts.csswg.org/css-grid/#z-order + * + * Flex items also have the same special-case described in + * https://drafts.csswg.org/css-flexbox/#painting + */ + static DisplayChildFlags DisplayFlagsForFlexOrGridItem() { + return DisplayChildFlags{DisplayChildFlag::ForcePseudoStackingContext}; + } + + bool RefusedAsyncAnimation() const { + return GetProperty(RefusedAsyncAnimationProperty()); + } + + /** + * Returns true if this frame is transformed (e.g. has CSS, SVG, or custom + * transforms) or if its parent is an SVG frame that has children-only + * transforms (e.g. an SVG viewBox attribute) or if its transform-style is + * preserve-3d or the frame has transform animations. + */ + bool IsTransformed() const; + + /** + * Same as IsTransformed, except that it doesn't take SVG transforms + * into account. + */ + bool IsCSSTransformed() const; + + /** + * True if this frame has any animation of transform in effect. + */ + bool HasAnimationOfTransform() const; + + /** + * True if this frame has any animation of opacity in effect. + * + * EffectSet is just an optimization. + */ + bool HasAnimationOfOpacity(mozilla::EffectSet* = nullptr) const; + + /** + * Returns true if the frame is translucent or the frame has opacity + * animations for the purposes of creating a stacking context. + * + * @param aStyleDisplay: This function needs style display struct. + * + * @param aStyleEffects: This function needs style effects struct. + * + * @param aEffectSet: This function may need to look up EffectSet property. + * If a caller already have one, pass it in can save property look up + * time; otherwise, just leave it as nullptr. + */ + bool HasOpacity(const nsStyleDisplay* aStyleDisplay, + const nsStyleEffects* aStyleEffects, + mozilla::EffectSet* aEffectSet = nullptr) const { + return HasOpacityInternal(1.0f, aStyleDisplay, aStyleEffects, aEffectSet); + } + /** + * Returns true if the frame is translucent for display purposes. + * + * @param aStyleDisplay: This function needs style display struct. + * + * @param aStyleEffects: This function needs style effects struct. + * + * @param aEffectSet: This function may need to look up EffectSet property. + * If a caller already have one, pass it in can save property look up + * time; otherwise, just leave it as nullptr. + */ + bool HasVisualOpacity(const nsStyleDisplay* aStyleDisplay, + const nsStyleEffects* aStyleEffects, + mozilla::EffectSet* aEffectSet = nullptr) const { + // Treat an opacity value of 0.99 and above as opaque. This is an + // optimization aimed at Web content which use opacity:0.99 as a hint for + // creating a stacking context only. + return HasOpacityInternal(0.99f, aStyleDisplay, aStyleEffects, aEffectSet); + } + + /** + * Returns a matrix (in pixels) for the current frame. The matrix should be + * relative to the current frame's coordinate space. + * + * @param aFrame The frame to compute the transform for. + * @param aAppUnitsPerPixel The number of app units per graphics unit. + */ + using ComputeTransformFunction = Matrix4x4 (*)(const nsIFrame*, + float aAppUnitsPerPixel); + /** Returns the transform getter of this frame, if any. */ + virtual ComputeTransformFunction GetTransformGetter() const { + return nullptr; + } + + /** + * Returns true if this frame is an SVG frame that has SVG transforms applied + * to it, or if its parent frame is an SVG frame that has children-only + * transforms (e.g. an SVG viewBox attribute). + * If aOwnTransforms is non-null and the frame has its own SVG transforms, + * aOwnTransforms will be set to these transforms. If aFromParentTransforms + * is non-null and the frame has an SVG parent with children-only transforms, + * then aFromParentTransforms will be set to these transforms. + */ + virtual bool IsSVGTransformed(Matrix* aOwnTransforms = nullptr, + Matrix* aFromParentTransforms = nullptr) const; + + /** + * Returns whether this frame will attempt to extend the 3d transforms of its + * children. This requires transform-style: preserve-3d, as well as no + * clipping or svg effects. + * + * @param aStyleDisplay: If the caller has this->StyleDisplay(), providing + * it here will improve performance. + * + * @param aStyleEffects: If the caller has this->StyleEffects(), providing + * it here will improve performance. + * + * @param aEffectSetForOpacity: This function may need to look up the + * EffectSet for opacity animations on this frame. + * If the caller already has looked up this EffectSet, it may pass it in to + * save an extra property lookup. + */ + bool Extend3DContext( + const nsStyleDisplay* aStyleDisplay, const nsStyleEffects* aStyleEffects, + mozilla::EffectSet* aEffectSetForOpacity = nullptr) const; + bool Extend3DContext( + mozilla::EffectSet* aEffectSetForOpacity = nullptr) const { + return Extend3DContext(StyleDisplay(), StyleEffects(), + aEffectSetForOpacity); + } + + /** + * Returns whether this frame has a parent that Extend3DContext() and has + * its own transform (or hidden backface) to be combined with the parent's + * transform. + */ + bool Combines3DTransformWithAncestors() const; + + /** + * Returns whether this frame has a hidden backface and has a parent that + * Extend3DContext(). This is useful because in some cases the hidden + * backface can safely be ignored if it could not be visible anyway. + * + */ + bool In3DContextAndBackfaceIsHidden() const; + + bool IsPreserve3DLeaf(const nsStyleDisplay* aStyleDisplay, + mozilla::EffectSet* aEffectSet = nullptr) const { + return Combines3DTransformWithAncestors() && + !Extend3DContext(aStyleDisplay, StyleEffects(), aEffectSet); + } + bool IsPreserve3DLeaf(mozilla::EffectSet* aEffectSet = nullptr) const { + return IsPreserve3DLeaf(StyleDisplay(), aEffectSet); + } + + bool HasPerspective() const; + + bool ChildrenHavePerspective(const nsStyleDisplay* aStyleDisplay) const; + bool ChildrenHavePerspective() const { + return ChildrenHavePerspective(StyleDisplay()); + } + + /** + * Includes the overflow area of all descendants that participate in the + * current 3d context into aOverflowAreas. + */ + void ComputePreserve3DChildrenOverflow( + mozilla::OverflowAreas& aOverflowAreas); + + void RecomputePerspectiveChildrenOverflow(const nsIFrame* aStartFrame); + + /** + * Returns whether z-index applies to this frame. + */ + bool ZIndexApplies() const; + + /** + * Returns the computed z-index for this frame, returning Nothing() for + * z-index: auto, and for frames that don't support z-index. + */ + Maybe<int32_t> ZIndex() const; + + /** + * Returns whether this frame is the anchor of some ancestor scroll frame. As + * this frame is moved, the scroll frame will apply adjustments to keep this + * scroll frame in the same relative position. + * + * aOutContainer will optionally be set to the scroll anchor container for + * this frame if this frame is an anchor. + */ + bool IsScrollAnchor( + mozilla::layout::ScrollAnchorContainer** aOutContainer = nullptr); + + /** + * Returns whether this frame is the anchor of some ancestor scroll frame, or + * has a descendant which is the scroll anchor. + */ + bool IsInScrollAnchorChain() const; + void SetInScrollAnchorChain(bool aInChain); + + /** + * Returns the number of ancestors between this and the root of our frame tree + */ + uint32_t GetDepthInFrameTree() const; + + /** + * Event handling of GUI events. + * + * @param aEvent event structure describing the type of event and rge widget + * where the event originated. The |point| member of this is in the coordinate + * system of the view returned by GetOffsetFromView. + * + * @param aEventStatus a return value indicating whether the event was + * handled and whether default processing should be done + * + * XXX From a frame's perspective it's unclear what the effect of the event + * status is. Does it cause the event to continue propagating through the + * frame hierarchy or is it just returned to the widgets? + * + * @see WidgetGUIEvent + * @see nsEventStatus + */ + MOZ_CAN_RUN_SCRIPT_BOUNDARY + virtual nsresult HandleEvent(nsPresContext* aPresContext, + mozilla::WidgetGUIEvent* aEvent, + nsEventStatus* aEventStatus); + + /** + * Search for selectable content at point and attempt to select + * based on the start and end selection behaviours. + * + * @param aPresContext Presentation context + * @param aPoint Point at which selection will occur. Coordinates + * should be relative to this frame. + * @param aBeginAmountType, aEndAmountType Selection behavior, see + * nsIFrame for definitions. + * @param aSelectFlags Selection flags defined in nsIFrame.h. + * @return success or failure at finding suitable content to select. + */ + MOZ_CAN_RUN_SCRIPT nsresult + SelectByTypeAtPoint(nsPresContext* aPresContext, const nsPoint& aPoint, + nsSelectionAmount aBeginAmountType, + nsSelectionAmount aEndAmountType, uint32_t aSelectFlags); + + MOZ_CAN_RUN_SCRIPT nsresult PeekBackwardAndForward( + nsSelectionAmount aAmountBack, nsSelectionAmount aAmountForward, + int32_t aStartPos, bool aJumpLines, uint32_t aSelectFlags); + + enum { SELECT_ACCUMULATE = 0x01 }; + + protected: + // Fire DOM event. If no aContent argument use frame's mContent. + void FireDOMEvent(const nsAString& aDOMEventName, + nsIContent* aContent = nullptr); + + // Selection Methods + + MOZ_CAN_RUN_SCRIPT_BOUNDARY NS_IMETHOD + HandlePress(nsPresContext* aPresContext, mozilla::WidgetGUIEvent* aEvent, + nsEventStatus* aEventStatus); + + /** + * MoveCaretToEventPoint() moves caret at the point of aMouseEvent. + * + * @param aPresContext Must not be nullptr. + * @param aMouseEvent Must not be nullptr, the message must be + * eMouseDown and its button must be primary or + * middle button. + * @param aEventStatus [out] Must not be nullptr. This method ignores + * its initial value, but callees may refer it. + */ + MOZ_CAN_RUN_SCRIPT nsresult MoveCaretToEventPoint( + nsPresContext* aPresContext, mozilla::WidgetMouseEvent* aMouseEvent, + nsEventStatus* aEventStatus); + + MOZ_CAN_RUN_SCRIPT_BOUNDARY NS_IMETHOD HandleMultiplePress( + nsPresContext* aPresContext, mozilla::WidgetGUIEvent* aEvent, + nsEventStatus* aEventStatus, bool aControlHeld); + + /** + * @param aPresContext must be non-nullptr. + * @param aEvent must be non-nullptr. + * @param aEventStatus must be non-nullptr. + */ + MOZ_CAN_RUN_SCRIPT + NS_IMETHOD HandleDrag(nsPresContext* aPresContext, + mozilla::WidgetGUIEvent* aEvent, + nsEventStatus* aEventStatus); + + MOZ_CAN_RUN_SCRIPT_BOUNDARY NS_IMETHOD + HandleRelease(nsPresContext* aPresContext, mozilla::WidgetGUIEvent* aEvent, + nsEventStatus* aEventStatus); + + // Test if we are selecting a table object: + // Most table/cell selection requires that Ctrl (Cmd on Mac) key is down + // during a mouse click or drag. Exception is using Shift+click when + // already in "table/cell selection mode" to extend a block selection + // Get the parent content node and offset of the frame + // of the enclosing cell or table (if not inside a cell) + // aTarget tells us what table element to select (currently only cell and + // table supported) (enums for this are defined in nsIFrame.h) + nsresult GetDataForTableSelection(const nsFrameSelection* aFrameSelection, + mozilla::PresShell* aPresShell, + mozilla::WidgetMouseEvent* aMouseEvent, + nsIContent** aParentContent, + int32_t* aContentOffset, + mozilla::TableSelectionMode* aTarget); + + /** + * @return see nsISelectionController.idl's `getDisplaySelection`. + */ + int16_t DetermineDisplaySelection(); + + public: + virtual nsresult GetContentForEvent(const mozilla::WidgetEvent* aEvent, + nsIContent** aContent); + + // This structure keeps track of the content node and offsets associated with + // a point; there is a primary and a secondary offset associated with any + // point. The primary and secondary offsets differ when the point is over a + // non-text object. The primary offset is the expected position of the + // cursor calculated from a point; the secondary offset, when it is different, + // indicates that the point is in the boundaries of some selectable object. + // Note that the primary offset can be after the secondary offset; for places + // that need the beginning and end of the object, the StartOffset and + // EndOffset helpers can be used. + struct MOZ_STACK_CLASS ContentOffsets { + ContentOffsets() + : offset(0), + secondaryOffset(0), + associate(mozilla::CARET_ASSOCIATE_BEFORE) {} + bool IsNull() { return !content; } + // Helpers for places that need the ends of the offsets and expect them in + // numerical order, as opposed to wanting the primary and secondary offsets + int32_t StartOffset() { return std::min(offset, secondaryOffset); } + int32_t EndOffset() { return std::max(offset, secondaryOffset); } + + nsCOMPtr<nsIContent> content; + int32_t offset; + int32_t secondaryOffset; + // This value indicates whether the associated content is before or after + // the offset; the most visible use is to allow the caret to know which line + // to display on. + mozilla::CaretAssociationHint associate; + }; + enum { + IGNORE_SELECTION_STYLE = 0x01, + // Treat visibility:hidden frames as non-selectable + SKIP_HIDDEN = 0x02 + }; + /** + * This function calculates the content offsets for selection relative to + * a point. Note that this should generally only be callled on the event + * frame associated with an event because this function does not account + * for frame lists other than the primary one. + * @param aPoint point relative to this frame + */ + ContentOffsets GetContentOffsetsFromPoint(const nsPoint& aPoint, + uint32_t aFlags = 0); + + virtual ContentOffsets GetContentOffsetsFromPointExternal( + const nsPoint& aPoint, uint32_t aFlags = 0) { + return GetContentOffsetsFromPoint(aPoint, aFlags); + } + + // Helper for GetContentAndOffsetsFromPoint; calculation of content offsets + // in this function assumes there is no child frame that can be targeted. + virtual ContentOffsets CalcContentOffsetsFromFramePoint( + const nsPoint& aPoint); + + /** + * Ensure that `this` gets notifed when `aImage`s underlying image request + * loads or animates. + * + * This in practice is only needed for the canvas frame and table cell + * backgrounds, which are the only cases that should paint a background that + * isn't its own. The canvas paints the background from the root element or + * body, and the table cell paints the background for its row. + * + * For regular frames, this is done in DidSetComputedStyle. + * + * NOTE: It's unclear if we even actually _need_ this for the second case, as + * invalidating the row should invalidate all the cells. For the canvas case + * this is definitely needed as it paints the background from somewhere "down" + * in the frame tree. + * + * Returns whether the image was in fact associated with the frame. + */ + [[nodiscard]] bool AssociateImage(const mozilla::StyleImage&); + + /** + * This needs to be called if the above caller returned true, once the above + * caller doesn't care about getting notified anymore. + */ + void DisassociateImage(const mozilla::StyleImage&); + + mozilla::StyleImageRendering UsedImageRendering() const; + mozilla::StyleTouchAction UsedTouchAction() const; + + enum class AllowCustomCursorImage { + No, + Yes, + }; + + /** + * This structure holds information about a cursor. AllowCustomCursorImage + * is `No`, then no cursor image should be loaded from the style specified on + * `mStyle`, or the frame's style. + * + * The `mStyle` member is used for `<area>` elements. + */ + struct MOZ_STACK_CLASS Cursor { + mozilla::StyleCursorKind mCursor = mozilla::StyleCursorKind::Auto; + AllowCustomCursorImage mAllowCustomCursor = AllowCustomCursorImage::Yes; + RefPtr<mozilla::ComputedStyle> mStyle; + }; + + /** + * Get the cursor for a given frame. + */ + virtual Maybe<Cursor> GetCursor(const nsPoint&); + + /** + * Get a point (in the frame's coordinate space) given an offset into + * the content. This point should be on the baseline of text with + * the correct horizontal offset + */ + virtual nsresult GetPointFromOffset(int32_t inOffset, nsPoint* outPoint); + + /** + * Get a list of character rects in a given range. + * This is similar version of GetPointFromOffset. + */ + virtual nsresult GetCharacterRectsInRange(int32_t aInOffset, int32_t aLength, + nsTArray<nsRect>& aRects); + + /** + * Get the child frame of this frame which contains the given + * content offset. outChildFrame may be this frame, or nullptr on return. + * outContentOffset returns the content offset relative to the start + * of the returned node. You can also pass a hint which tells the method + * to stick to the end of the first found frame or the beginning of the + * next in case the offset falls on a boundary. + */ + virtual nsresult GetChildFrameContainingOffset( + int32_t inContentOffset, + bool inHint, // false stick left + int32_t* outFrameContentOffset, nsIFrame** outChildFrame); + + /** + * Get the current frame-state value for this frame. aResult is + * filled in with the state bits. + */ + nsFrameState GetStateBits() const { return mState; } + + /** + * Update the current frame-state value for this frame. + */ + void AddStateBits(nsFrameState aBits) { mState |= aBits; } + void RemoveStateBits(nsFrameState aBits) { mState &= ~aBits; } + void AddOrRemoveStateBits(nsFrameState aBits, bool aVal) { + aVal ? AddStateBits(aBits) : RemoveStateBits(aBits); + } + + /** + * Checks if the current frame-state includes all of the listed bits + */ + bool HasAllStateBits(nsFrameState aBits) const { + return (mState & aBits) == aBits; + } + + /** + * Checks if the current frame-state includes any of the listed bits + */ + bool HasAnyStateBits(nsFrameState aBits) const { return mState & aBits; } + + private: + /** + * Called when this frame becomes primary for mContent. + */ + void InitPrimaryFrame(); + + public: + /** + * Return true if this frame is the primary frame for mContent. + */ + bool IsPrimaryFrame() const { return mIsPrimaryFrame; } + + void SetIsPrimaryFrame(bool aIsPrimary) { + mIsPrimaryFrame = aIsPrimary; + if (aIsPrimary) { + InitPrimaryFrame(); + } + } + + bool IsPrimaryFrameOfRootOrBodyElement() const; + + /** + * @return true if this frame is used as a fieldset's rendered legend. + */ + bool IsRenderedLegend() const; + + /** + * This call is invoked on the primary frame for a character data content + * node, when it is changed in the content tree. + */ + virtual nsresult CharacterDataChanged(const CharacterDataChangeInfo&); + + /** + * This call is invoked when the value of a content objects's attribute + * is changed. + * The first frame that maps that content is asked to deal + * with the change by doing whatever is appropriate. + * + * @param aNameSpaceID the namespace of the attribute + * @param aAttribute the atom name of the attribute + * @param aModType Whether or not the attribute was added, changed, or + * removed. The constants are defined in MutationEvent.webidl. + */ + virtual nsresult AttributeChanged(int32_t aNameSpaceID, nsAtom* aAttribute, + int32_t aModType); + + /** + * When the element states of mContent change, this method is invoked on the + * primary frame of that element. + * + * @param aStates the changed states + */ + virtual void ElementStateChanged(mozilla::dom::ElementState aStates); + + /** + * Continuation member functions + */ + virtual nsIFrame* GetPrevContinuation() const; + virtual void SetPrevContinuation(nsIFrame*); + virtual nsIFrame* GetNextContinuation() const; + virtual void SetNextContinuation(nsIFrame*); + virtual nsIFrame* FirstContinuation() const { + return const_cast<nsIFrame*>(this); + } + virtual nsIFrame* LastContinuation() const { + return const_cast<nsIFrame*>(this); + } + + /** + * GetTailContinuation gets the last non-overflow-container continuation + * in the continuation chain, i.e. where the next sibling element + * should attach). + */ + nsIFrame* GetTailContinuation(); + + /** + * Flow member functions + */ + virtual nsIFrame* GetPrevInFlow() const; + virtual void SetPrevInFlow(nsIFrame*); + + virtual nsIFrame* GetNextInFlow() const; + virtual void SetNextInFlow(nsIFrame*); + + /** + * Return the first frame in our current flow. + */ + virtual nsIFrame* FirstInFlow() const { return const_cast<nsIFrame*>(this); } + + /** + * Return the last frame in our current flow. + */ + virtual nsIFrame* LastInFlow() const { return const_cast<nsIFrame*>(this); } + + /** + * Note: "width" in the names and comments on the following methods + * means inline-size, which could be height in vertical layout + */ + + /** + * Mark any stored intrinsic width information as dirty (requiring + * re-calculation). Note that this should generally not be called + * directly; PresShell::FrameNeedsReflow() will call it instead. + */ + virtual void MarkIntrinsicISizesDirty(); + + public: + /** + * Make this frame and all descendants dirty (if not already). + * Exceptions: TableColGroupFrame children. + */ + void MarkSubtreeDirty(); + + /** + * Get the min-content intrinsic inline size of the frame. This must be + * less than or equal to the max-content intrinsic inline size. + * + * This is *not* affected by the CSS 'min-width', 'width', and + * 'max-width' properties on this frame, but it is affected by the + * values of those properties on this frame's descendants. (It may be + * called during computation of the values of those properties, so it + * cannot depend on any values in the nsStylePosition for this frame.) + * + * The value returned should **NOT** include the space required for + * padding and border. + * + * Note that many frames will cache the result of this function call + * unless MarkIntrinsicISizesDirty is called. + * + * It is not acceptable for a frame to mark itself dirty when this + * method is called. + * + * This method must not return a negative value. + */ + virtual nscoord GetMinISize(gfxContext* aRenderingContext); + + /** + * Get the max-content intrinsic inline size of the frame. This must be + * greater than or equal to the min-content intrinsic inline size. + * + * Otherwise, all the comments for |GetMinISize| above apply. + */ + virtual nscoord GetPrefISize(gfxContext* aRenderingContext); + + /** + * |InlineIntrinsicISize| represents the intrinsic width information + * in inline layout. Code that determines the intrinsic width of a + * region of inline layout accumulates the result into this structure. + * This pattern is needed because we need to maintain state + * information about whitespace (for both collapsing and trimming). + */ + struct InlineIntrinsicISizeData { + InlineIntrinsicISizeData() + : mLine(nullptr), + mLineContainer(nullptr), + mPrevLines(0), + mCurrentLine(0), + mTrailingWhitespace(0), + mSkipWhitespace(true) {} + + // The line. This may be null if the inlines are not associated with + // a block or if we just don't know the line. + const nsLineList_iterator* mLine; + + // The line container. Private, to ensure we always use SetLineContainer + // to update it. + // + // Note that nsContainerFrame::DoInlineIntrinsicISize will clear the + // |mLine| and |mLineContainer| fields when following a next-in-flow link, + // so we must not assume these can always be dereferenced. + private: + nsIFrame* mLineContainer; + + // Setter and getter for the lineContainer field: + public: + void SetLineContainer(nsIFrame* aLineContainer) { + mLineContainer = aLineContainer; + } + nsIFrame* LineContainer() const { return mLineContainer; } + + // The maximum intrinsic width for all previous lines. + nscoord mPrevLines; + + // The maximum intrinsic width for the current line. At a line + // break (mandatory for preferred width; allowed for minimum width), + // the caller should call |Break()|. + nscoord mCurrentLine; + + // This contains the width of the trimmable whitespace at the end of + // |mCurrentLine|; it is zero if there is no such whitespace. + nscoord mTrailingWhitespace; + + // True if initial collapsable whitespace should be skipped. This + // should be true at the beginning of a block, after hard breaks + // and when the last text ended with whitespace. + bool mSkipWhitespace; + + // Floats encountered in the lines. + class FloatInfo { + public: + FloatInfo(const nsIFrame* aFrame, nscoord aWidth) + : mFrame(aFrame), mWidth(aWidth) {} + const nsIFrame* Frame() const { return mFrame; } + nscoord Width() const { return mWidth; } + + private: + const nsIFrame* mFrame; + nscoord mWidth; + }; + + nsTArray<FloatInfo> mFloats; + }; + + struct InlineMinISizeData : public InlineIntrinsicISizeData { + InlineMinISizeData() : mAtStartOfLine(true) {} + + // The default implementation for nsIFrame::AddInlineMinISize. + void DefaultAddInlineMinISize(nsIFrame* aFrame, nscoord aISize, + bool aAllowBreak = true); + + // We need to distinguish forced and optional breaks for cases where the + // current line total is negative. When it is, we need to ignore + // optional breaks to prevent min-width from ending up bigger than + // pref-width. + void ForceBreak(); + + // If the break here is actually taken, aHyphenWidth must be added to the + // width of the current line. + void OptionallyBreak(nscoord aHyphenWidth = 0); + + // Whether we're currently at the start of the line. If we are, we + // can't break (for example, between the text-indent and the first + // word). + bool mAtStartOfLine; + }; + + struct InlinePrefISizeData : public InlineIntrinsicISizeData { + InlinePrefISizeData() : mLineIsEmpty(true) {} + + /** + * Finish the current line and start a new line. + * + * @param aClearType controls whether isize of floats are considered + * and what floats are kept for the next line: + * * |None| skips handling floats, which means no floats are + * removed, and isizes of floats are not considered either. + * * |Both| takes floats into consideration when computing isize + * of the current line, and removes all floats after that. + * * |Left| and |Right| do the same as |Both| except that they only + * remove floats on the given side, and any floats on the other + * side that are prior to a float on the given side that has a + * 'clear' property that clears them. + */ + void ForceBreak(mozilla::StyleClear aClearType = mozilla::StyleClear::Both); + + // The default implementation for nsIFrame::AddInlinePrefISize. + void DefaultAddInlinePrefISize(nscoord aISize); + + // True if the current line contains nothing other than placeholders. + bool mLineIsEmpty; + }; + + /** + * Add the intrinsic minimum width of a frame in a way suitable for + * use in inline layout to an |InlineIntrinsicISizeData| object that + * represents the intrinsic width information of all the previous + * frames in the inline layout region. + * + * All *allowed* breakpoints within the frame determine what counts as + * a line for the |InlineIntrinsicISizeData|. This means that + * |aData->mTrailingWhitespace| will always be zero (unlike for + * AddInlinePrefISize). + * + * All the comments for |GetMinISize| apply, except that this function + * is responsible for adding padding, border, and margin and for + * considering the effects of 'width', 'min-width', and 'max-width'. + * + * This may be called on any frame. Frames that do not participate in + * line breaking can inherit the default implementation on nsFrame, + * which calls |GetMinISize|. + */ + virtual void AddInlineMinISize(gfxContext* aRenderingContext, + InlineMinISizeData* aData); + + /** + * Add the intrinsic preferred width of a frame in a way suitable for + * use in inline layout to an |InlineIntrinsicISizeData| object that + * represents the intrinsic width information of all the previous + * frames in the inline layout region. + * + * All the comments for |AddInlineMinISize| and |GetPrefISize| apply, + * except that this fills in an |InlineIntrinsicISizeData| structure + * based on using all *mandatory* breakpoints within the frame. + */ + virtual void AddInlinePrefISize(gfxContext* aRenderingContext, + InlinePrefISizeData* aData); + + /** + * Intrinsic size of a frame in a single axis. + * + * This can represent either isize or bsize. + */ + struct IntrinsicSizeOffsetData { + nscoord padding = 0; + nscoord border = 0; + nscoord margin = 0; + nscoord BorderPadding() const { return border + padding; }; + }; + + /** + * Return the isize components of padding, border, and margin + * that contribute to the intrinsic width that applies to the parent. + * @param aPercentageBasis the percentage basis to use for padding/margin - + * i.e. the Containing Block's inline-size + */ + virtual IntrinsicSizeOffsetData IntrinsicISizeOffsets( + nscoord aPercentageBasis = NS_UNCONSTRAINEDSIZE); + + /** + * Return the bsize components of padding, border, and margin + * that contribute to the intrinsic width that applies to the parent. + * @param aPercentageBasis the percentage basis to use for padding/margin - + * i.e. the Containing Block's inline-size + */ + IntrinsicSizeOffsetData IntrinsicBSizeOffsets( + nscoord aPercentageBasis = NS_UNCONSTRAINEDSIZE); + + virtual mozilla::IntrinsicSize GetIntrinsicSize(); + + /** + * Get the preferred aspect ratio of this frame, or a default-constructed + * AspectRatio if it has none. + * + * https://drafts.csswg.org/css-sizing-4/#preferred-aspect-ratio + */ + mozilla::AspectRatio GetAspectRatio() const; + + /** + * Get the intrinsic aspect ratio of this frame, or a default-constructed + * AspectRatio if it has no intrinsic ratio. + * + * The intrinsic ratio is the ratio of the width/height of a box with an + * intrinsic size or the intrinsic aspect ratio of a scalable vector image + * without an intrinsic size. A frame class implementing a replaced element + * should override this method if it has a intrinsic ratio. + */ + virtual mozilla::AspectRatio GetIntrinsicRatio() const; + + /** + * Compute the size that a frame will occupy. Called while + * constructing the ReflowInput to be used to Reflow the frame, + * in order to fill its mComputedWidth and mComputedHeight member + * variables. + * + * Note that the reason that border and padding need to be passed + * separately is so that the 'box-sizing' property can be handled. + * Thus aMargin includes absolute positioning offsets as well. + * + * @param aWM The writing mode to use for the returned size (need not match + * this frame's writing mode). This is also the writing mode of + * the passed-in LogicalSize parameters. + * @param aCBSize The size of the element's containing block. (Well, + * the BSize() component isn't really.) + * @param aAvailableISize The available inline-size for 'auto' inline-size. + * This is usually the same as aCBSize.ISize(), + * but differs in cases such as block + * formatting context roots next to floats, or + * in some cases of float reflow in quirks + * mode. + * @param aMargin The sum of the inline / block margins ***AND*** + * absolute positioning offsets (inset-block and + * inset-inline) of the frame, including actual values + * resulting from percentages and from the + * "hypothetical box" for absolute positioning, but + * not including actual values resulting from 'auto' + * margins or ignored 'auto' values in absolute + * positioning. + * @param aBorderPadding The sum of the frame's inline / block border-widths + * and padding (including actual values resulting from + * percentage padding values). + * @param aSizeOverride Optional override values for size properties, which + * this function will use internally instead of the + * actual property values. + * @param aFlags Flags to further customize behavior (definitions in + * LayoutConstants.h). + * + * The return value includes the computed LogicalSize and AspectRatioUsage + * which indicates whether the inline/block size is affected by aspect-ratio + * or not. The BSize() of the returned LogicalSize may be + * NS_UNCONSTRAINEDSIZE, but the ISize() must not be. We need AspectRatioUsage + * during reflow because the final size may be affected by the content size + * after applying aspect-ratio. + * https://drafts.csswg.org/css-sizing-4/#aspect-ratio-minimum + * + */ + enum class AspectRatioUsage : uint8_t { + None, + ToComputeISize, + ToComputeBSize, + }; + struct SizeComputationResult { + mozilla::LogicalSize mLogicalSize; + AspectRatioUsage mAspectRatioUsage = AspectRatioUsage::None; + }; + virtual SizeComputationResult ComputeSize( + gfxContext* aRenderingContext, mozilla::WritingMode aWM, + const mozilla::LogicalSize& aCBSize, nscoord aAvailableISize, + const mozilla::LogicalSize& aMargin, + const mozilla::LogicalSize& aBorderPadding, + const mozilla::StyleSizeOverrides& aSizeOverrides, + mozilla::ComputeSizeFlags aFlags); + + protected: + /** + * A helper, used by |nsIFrame::ComputeSize| (for frames that need to + * override only this part of ComputeSize), that computes the size + * that should be returned when inline-size, block-size, and + * [min|max]-[inline-size|block-size] are all 'auto' or equivalent. + * + * In general, frames that can accept any computed inline-size/block-size + * should override only ComputeAutoSize, and frames that cannot do so need to + * override ComputeSize to enforce their inline-size/block-size invariants. + * + * Implementations may optimize by returning a garbage inline-size if + * StylePosition()->ISize() is not 'auto' (or inline-size override in + * aSizeOverrides is not 'auto' if provided), and likewise for BSize(), since + * in such cases the result is guaranteed to be unused. + * + * Most of the frame are not expected to check the aSizeOverrides parameter + * apart from checking the inline size override for 'auto' if they want to + * optimize and return garbage inline-size. + */ + virtual mozilla::LogicalSize ComputeAutoSize( + gfxContext* aRenderingContext, mozilla::WritingMode aWM, + const mozilla::LogicalSize& aCBSize, nscoord aAvailableISize, + const mozilla::LogicalSize& aMargin, + const mozilla::LogicalSize& aBorderPadding, + const mozilla::StyleSizeOverrides& aSizeOverrides, + mozilla::ComputeSizeFlags aFlags); + + /** + * Utility function for ComputeAutoSize implementations. Return + * max(GetMinISize(), min(aISizeInCB, GetPrefISize())) + */ + nscoord ShrinkISizeToFit(gfxContext* aRenderingContext, nscoord aISizeInCB, + mozilla::ComputeSizeFlags aFlags); + + public: + /** + * Compute a tight bounding rectangle for the frame. This is a rectangle + * that encloses the pixels that are actually drawn. We're allowed to be + * conservative and currently we don't try very hard. The rectangle is + * in appunits and relative to the origin of this frame. + * + * This probably only needs to include frame bounds, glyph bounds, and + * text decorations, but today it sometimes includes other things that + * contribute to ink overflow. + * + * @param aDrawTarget a draw target that can be used if we need + * to do measurement + */ + virtual nsRect ComputeTightBounds(DrawTarget* aDrawTarget) const; + + /** + * This function is similar to GetPrefISize and ComputeTightBounds: it + * computes the left and right coordinates of a preferred tight bounding + * rectangle for the frame. This is a rectangle that would enclose the pixels + * that are drawn if we lay out the element without taking any optional line + * breaks. The rectangle is in appunits and relative to the origin of this + * frame. Currently, this function is only implemented for nsBlockFrame and + * nsTextFrame and is used to determine intrinsic widths of MathML token + * elements. + + * @param aContext a rendering context that can be used if we need + * to do measurement + * @param aX computed left coordinate of the tight bounding rectangle + * @param aXMost computed intrinsic width of the tight bounding rectangle + * + */ + virtual nsresult GetPrefWidthTightBounds(gfxContext* aContext, nscoord* aX, + nscoord* aXMost); + + /** + * The frame is given an available size and asked for its desired + * size. This is the frame's opportunity to reflow its children. + * + * If the frame has the NS_FRAME_IS_DIRTY bit set then it is + * responsible for completely reflowing itself and all of its + * descendants. + * + * Otherwise, if the frame has the NS_FRAME_HAS_DIRTY_CHILDREN bit + * set, then it is responsible for reflowing at least those + * children that have NS_FRAME_HAS_DIRTY_CHILDREN or NS_FRAME_IS_DIRTY + * set. + * + * If a difference in available size from the previous reflow causes + * the frame's size to change, it should reflow descendants as needed. + * + * Calculates the size of this frame after reflowing (calling Reflow on, and + * updating the size and position of) its children, as necessary. The + * calculated size is returned to the caller via the ReflowOutput + * outparam. (The caller is responsible for setting the actual size and + * position of this frame.) + * + * A frame's children must _all_ be reflowed if the frame is dirty (the + * NS_FRAME_IS_DIRTY bit is set on it). Otherwise, individual children + * must be reflowed if they are dirty or have the NS_FRAME_HAS_DIRTY_CHILDREN + * bit set on them. Otherwise, whether children need to be reflowed depends + * on the frame's type (it's up to individual Reflow methods), and on what + * has changed. For example, a change in the width of the frame may require + * all of its children to be reflowed (even those without dirty bits set on + * them), whereas a change in its height might not. + * (ReflowInput::ShouldReflowAllKids may be helpful in deciding whether + * to reflow all the children, but for some frame types it might result in + * over-reflow.) + * + * Note: if it's only the overflow rect(s) of a frame that need to be + * updated, then UpdateOverflow should be called instead of Reflow. + * + * @param aReflowOutput <i>out</i> parameter where you should return the + * desired size and ascent/descent info. You should include any + * space you want for border/padding in the desired size you return. + * + * It's okay to return a desired size that exceeds the avail + * size if that's the smallest you can be, i.e. it's your + * minimum size. + * + * For an incremental reflow you are responsible for invalidating + * any area within your frame that needs repainting (including + * borders). If your new desired size is different than your current + * size, then your parent frame is responsible for making sure that + * the difference between the two rects is repainted + * + * @param aReflowInput information about your reflow including the reason + * for the reflow and the available space in which to lay out. Each + * dimension of the available space can either be constrained or + * unconstrained (a value of NS_UNCONSTRAINEDSIZE). + * + * Note that the available space can be negative. In this case you + * still must return an accurate desired size. If you're a container + * you must <b>always</b> reflow at least one frame regardless of the + * available space + * + * @param aStatus a return value indicating whether the frame is complete + * and whether the next-in-flow is dirty and needs to be reflowed + */ + virtual void Reflow(nsPresContext* aPresContext, ReflowOutput& aReflowOutput, + const ReflowInput& aReflowInput, nsReflowStatus& aStatus); + + // Option flags for ReflowChild(), FinishReflowChild(), and + // SyncFrameViewAfterReflow(). + enum class ReflowChildFlags : uint32_t { + Default = 0, + + // Don't position the frame's view. Set this if you don't want to + // automatically sync the frame and view. + NoMoveView = 1 << 0, + + // Don't move the frame. Also implies NoMoveView. + NoMoveFrame = (1 << 1) | NoMoveView, + + // Don't size the frame's view. + NoSizeView = 1 << 2, + + // Only applies to ReflowChild; if true, don't delete the next-in-flow, even + // if the reflow is fully complete. + NoDeleteNextInFlowChild = 1 << 3, + + // Only applies to FinishReflowChild. Tell it to call + // ApplyRelativePositioning. + ApplyRelativePositioning = 1 << 4, + }; + + /** + * Post-reflow hook. After a frame is reflowed this method will be called + * informing the frame that this reflow process is complete, and telling the + * frame the status returned by the Reflow member function. + * + * This call may be invoked many times, while NS_FRAME_IN_REFLOW is set, + * before it is finally called once with a NS_FRAME_REFLOW_COMPLETE value. + * When called with a NS_FRAME_REFLOW_COMPLETE value the NS_FRAME_IN_REFLOW + * bit in the frame state will be cleared. + * + * XXX This doesn't make sense. If the frame is reflowed but not complete, + * then the status should have IsIncomplete() equal to true. + * XXX Don't we want the semantics to dictate that we only call this once for + * a given reflow? + */ + virtual void DidReflow(nsPresContext* aPresContext, + const ReflowInput* aReflowInput); + + void FinishReflowWithAbsoluteFrames(nsPresContext* aPresContext, + ReflowOutput& aDesiredSize, + const ReflowInput& aReflowInput, + nsReflowStatus& aStatus, + bool aConstrainBSize = true); + + /** + * Updates the overflow areas of the frame. This can be called if an + * overflow area of the frame's children has changed without reflowing. + * @return true if either of the overflow areas for this frame have changed. + */ + bool UpdateOverflow(); + + /** + * Computes any overflow area created by the frame itself (outside of the + * frame bounds) and includes it into aOverflowAreas. + * + * Returns false if updating overflow isn't supported for this frame. + * If the frame requires a reflow instead, then it is responsible + * for scheduling one. + */ + virtual bool ComputeCustomOverflow(mozilla::OverflowAreas& aOverflowAreas); + + /** + * Computes any overflow area created by children of this frame and + * includes it into aOverflowAreas. + */ + virtual void UnionChildOverflow(mozilla::OverflowAreas& aOverflowAreas); + + // Returns the applicable overflow-clip-margin values. + using PhysicalAxes = mozilla::PhysicalAxes; + + nsSize OverflowClipMargin(PhysicalAxes aClipAxes) const; + // Returns the axes on which this frame should apply overflow clipping. + PhysicalAxes ShouldApplyOverflowClipping(const nsStyleDisplay* aDisp) const; + + /** + * Helper method used by block reflow to identify runs of text so + * that proper word-breaking can be done. + * + * @return + * true if we can continue a "text run" through the frame. A + * text run is text that should be treated contiguously for line + * and word breaking. + */ + virtual bool CanContinueTextRun() const; + + /** + * Computes an approximation of the rendered text of the frame and its + * continuations. Returns nothing for non-text frames. + * The appended text will often not contain all the whitespace from source, + * depending on CSS white-space processing. + * if aEndOffset goes past end, use the text up to the string's end. + * Call this on the primary frame for a text node. + * aStartOffset and aEndOffset can be content offsets or offsets in the + * rendered text, depending on aOffsetType. + * Returns a string, as well as offsets identifying the start of the text + * within the rendered text for the whole node, and within the text content + * of the node. + */ + struct RenderedText { + nsAutoString mString; + uint32_t mOffsetWithinNodeRenderedText; + int32_t mOffsetWithinNodeText; + RenderedText() + : mOffsetWithinNodeRenderedText(0), mOffsetWithinNodeText(0) {} + }; + enum class TextOffsetType { + // Passed-in start and end offsets are within the content text. + OffsetsInContentText, + // Passed-in start and end offsets are within the rendered text. + OffsetsInRenderedText, + }; + enum class TrailingWhitespace { + Trim, + // Spaces preceding a caret at the end of a line should not be trimmed + DontTrim, + }; + virtual RenderedText GetRenderedText( + uint32_t aStartOffset = 0, uint32_t aEndOffset = UINT32_MAX, + TextOffsetType aOffsetType = TextOffsetType::OffsetsInContentText, + TrailingWhitespace aTrimTrailingWhitespace = TrailingWhitespace::Trim) { + return RenderedText(); + } + + /** + * Returns true if the frame contains any non-collapsed characters. + * This method is only available for text frames, and it will return false + * for all other frame types. + */ + virtual bool HasAnyNoncollapsedCharacters() { return false; } + + /** + * Returns true if events of the given type targeted at this frame + * should only be dispatched to the system group. + */ + virtual bool OnlySystemGroupDispatch(mozilla::EventMessage aMessage) const { + return false; + } + + // + // Accessor functions to an associated view object: + // + bool HasView() const { return !!(mState & NS_FRAME_HAS_VIEW); } + + // Returns true iff this frame's computed block-size property is one of the + // intrinsic-sizing keywords. + bool HasIntrinsicKeywordForBSize() const { + const auto& bSize = StylePosition()->BSize(GetWritingMode()); + return bSize.IsFitContent() || bSize.IsMinContent() || + bSize.IsMaxContent() || bSize.IsFitContentFunction(); + } + /** + * Helper method to create a view for a frame. Only used by a few sub-classes + * that need a view. + */ + void CreateView(); + + protected: + virtual nsView* GetViewInternal() const { + MOZ_ASSERT_UNREACHABLE("method should have been overridden by subclass"); + return nullptr; + } + virtual void SetViewInternal(nsView* aView) { + MOZ_ASSERT_UNREACHABLE("method should have been overridden by subclass"); + } + + public: + nsView* GetView() const { + if (MOZ_LIKELY(!HasView())) { + return nullptr; + } + nsView* view = GetViewInternal(); + MOZ_ASSERT(view, "GetViewInternal() should agree with HasView()"); + return view; + } + void SetView(nsView* aView); + + /** + * Find the closest view (on |this| or an ancestor). + * If aOffset is non-null, it will be set to the offset of |this| + * from the returned view. + */ + nsView* GetClosestView(nsPoint* aOffset = nullptr) const; + + /** + * Find the closest ancestor (excluding |this| !) that has a view + */ + nsIFrame* GetAncestorWithView() const; + + /** + * Sets the view's attributes from the frame style. + * Call this for nsChangeHint_SyncFrameView style changes or when the view + * has just been created. + * @param aView the frame's view or use GetView() if nullptr is given + */ + void SyncFrameViewProperties(nsView* aView = nullptr); + + /** + * Get the offset between the coordinate systems of |this| and aOther. + * Adding the return value to a point in the coordinate system of |this| + * will transform the point to the coordinate system of aOther. + * + * aOther must be non-null. + * + * This function is fastest when aOther is an ancestor of |this|. + * + * This function _DOES NOT_ work across document boundaries. + * Use this function only when |this| and aOther are in the same document. + * + * NOTE: this actually returns the offset from aOther to |this|, but + * that offset is added to transform _coordinates_ from |this| to + * aOther. + */ + nsPoint GetOffsetTo(const nsIFrame* aOther) const; + + /** + * Just like GetOffsetTo, but treats all scrollframes as scrolled to + * their origin. + */ + nsPoint GetOffsetToIgnoringScrolling(const nsIFrame* aOther) const; + + /** + * Get the offset between the coordinate systems of |this| and aOther + * expressed in appunits per dev pixel of |this|' document. Adding the return + * value to a point that is relative to the origin of |this| will make the + * point relative to the origin of aOther but in the appunits per dev pixel + * ratio of |this|. + * + * aOther must be non-null. + * + * This function is fastest when aOther is an ancestor of |this|. + * + * This function works across document boundaries. + * + * Because this function may cross document boundaries that have different + * app units per dev pixel ratios it needs to be used very carefully. + * + * NOTE: this actually returns the offset from aOther to |this|, but + * that offset is added to transform _coordinates_ from |this| to + * aOther. + */ + nsPoint GetOffsetToCrossDoc(const nsIFrame* aOther) const; + + /** + * Like GetOffsetToCrossDoc, but the caller can specify which appunits + * to return the result in. + */ + nsPoint GetOffsetToCrossDoc(const nsIFrame* aOther, const int32_t aAPD) const; + + /** + * Get the rect of the frame relative to the top-left corner of the + * screen in CSS pixels. + * @return the CSS pixel rect of the frame relative to the top-left + * corner of the screen. + */ + mozilla::CSSIntRect GetScreenRect() const; + + /** + * Get the screen rect of the frame in app units. + * @return the app unit rect of the frame in screen coordinates. + */ + nsRect GetScreenRectInAppUnits() const; + + /** + * Returns the offset from this frame to the closest geometric parent that + * has a view. Also returns the containing view or null in case of error + */ + void GetOffsetFromView(nsPoint& aOffset, nsView** aView) const; + + /** + * Returns the nearest widget containing this frame. If this frame has a + * view and the view has a widget, then this frame's widget is + * returned, otherwise this frame's geometric parent is checked + * recursively upwards. + */ + nsIWidget* GetNearestWidget() const; + + /** + * Whether the frame is a subgrid right now. + */ + bool IsSubgrid() const; + + /** + * Same as GetNearestWidget() above but uses an outparam to return the offset + * of this frame to the returned widget expressed in appunits of |this| (the + * widget might be in a different document with a different zoom). + */ + nsIWidget* GetNearestWidget(nsPoint& aOffset) const; + + /** + * Whether the content for this frame is disabled, used for event handling. + */ + bool IsContentDisabled() const; + + enum class IncludeContentVisibility { + Auto, + Hidden, + }; + + constexpr static mozilla::EnumSet<IncludeContentVisibility> + IncludeAllContentVisibility() { + return {IncludeContentVisibility::Auto, IncludeContentVisibility::Hidden}; + } + + /** + * Returns true if this frame's `content-visibility: auto` element is + * considered relevant content. + */ + bool IsContentRelevant() const; + + /** + * Whether this frame hides its contents via the `content-visibility` + * property. + * @param aInclude specifies what kind of `content-visibility` to include. + */ + bool HidesContent(const mozilla::EnumSet<IncludeContentVisibility>& = + IncludeAllContentVisibility()) const; + + /** + * Whether this frame hides its contents via the `content-visibility` + * property, while doing layout. This might be true when `HidesContent()` is + * true in the case that hidden content is being forced to lay out by position + * or size queries from script. + */ + bool HidesContentForLayout() const; + + /** + * Returns true if this frame is entirely hidden due the `content-visibility` + * property on an ancestor. + * @param aInclude specifies what kind of `content-visibility` to include. + */ + bool IsHiddenByContentVisibilityOnAnyAncestor( + const mozilla::EnumSet<IncludeContentVisibility>& = + IncludeAllContentVisibility()) const; + + /** + * Returns true is this frame is hidden by its first unskipped in flow + * ancestor due to `content-visibility`. + */ + bool IsHiddenByContentVisibilityOfInFlowParentForLayout() const; + + /** + * Whether or not this frame's content is a descendant of a top layer element + * used to determine if this frame is relevant content for + * `content-visibility: auto`. + */ + bool IsDescendantOfTopLayerElement() const; + + /** + * Returns true if this frame has a SelectionType::eNormal type selection in + * somewhere in its subtree of frames. This is used to determine content + * relevancy for `content-visibility: auto`. + */ + bool HasSelectionInSubtree(); + + /** + * Update the whether or not this frame is considered relevant content for the + * purposes of `content-visibility: auto` according to the rules specified in + * https://drafts.csswg.org/css-contain-2/#relevant-to-the-user. + */ + void UpdateIsRelevantContent(const ContentRelevancy& aRelevancyToUpdate); + + /** + * Get the "type" of the frame. + * + * @see mozilla::LayoutFrameType + */ + mozilla::LayoutFrameType Type() const { + MOZ_ASSERT(uint8_t(mClass) < mozilla::ArrayLength(sLayoutFrameTypes)); + return sLayoutFrameTypes[uint8_t(mClass)]; + } + +#ifdef __GNUC__ +# pragma GCC diagnostic push +# pragma GCC diagnostic ignored "-Wtype-limits" +#endif +#ifdef __clang__ +# pragma clang diagnostic push +# pragma clang diagnostic ignored "-Wunknown-pragmas" +# pragma clang diagnostic ignored "-Wtautological-unsigned-zero-compare" +#endif + +#define FRAME_TYPE(name_, first_class_, last_class_) \ + bool Is##name_##Frame() const { \ + return uint8_t(mClass) >= uint8_t(ClassID::first_class_##_id) && \ + uint8_t(mClass) <= uint8_t(ClassID::last_class_##_id); \ + } +#include "mozilla/FrameTypeList.h" +#undef FRAME_TYPE + +#ifdef __GNUC__ +# pragma GCC diagnostic pop +#endif +#ifdef __clang__ +# pragma clang diagnostic pop +#endif + + /** + * Returns a transformation matrix that converts points in this frame's + * coordinate space to points in some ancestor frame's coordinate space. + * The frame decides which ancestor it will use as a reference point. + * If this frame has no ancestor, aOutAncestor will be set to null. + * + * @param aViewportType specifies whether the starting point is layout + * or visual coordinates + * @param aStopAtAncestor don't look further than aStopAtAncestor. If null, + * all ancestors (including across documents) will be traversed. + * @param aOutAncestor [out] The ancestor frame the frame has chosen. If + * this frame has no ancestor, *aOutAncestor will be set to null. If + * this frame is not a root frame, then *aOutAncestor will be in the same + * document as this frame. If this frame IsTransformed(), then *aOutAncestor + * will be the parent frame (if not preserve-3d) or the nearest + * non-transformed ancestor (if preserve-3d). + * @return A Matrix4x4 that converts points in the coordinate space + * RelativeTo{this, aViewportType} into points in aOutAncestor's + * coordinate space. + */ + enum { + IN_CSS_UNITS = 1 << 0, + STOP_AT_STACKING_CONTEXT_AND_DISPLAY_PORT = 1 << 1 + }; + Matrix4x4Flagged GetTransformMatrix(mozilla::ViewportType aViewportType, + mozilla::RelativeTo aStopAtAncestor, + nsIFrame** aOutAncestor, + uint32_t aFlags = 0) const; + + /** + * Bit-flags to pass to IsFrameOfType() + */ + enum { + eMathML = 1 << 0, + eSVG = 1 << 1, + eSVGContainer = 1 << 2, + eBidiInlineContainer = 1 << 3, + // the frame is for a replaced element, such as an image + eReplaced = 1 << 4, + // Frame that contains a block but looks like a replaced element + // from the outside + eReplacedContainsBlock = 1 << 5, + // A frame that participates in inline reflow, i.e., one that + // requires ReflowInput::mLineLayout. + eLineParticipant = 1 << 6, + eCanContainOverflowContainers = 1 << 7, + eTablePart = 1 << 8, + eSupportsCSSTransforms = 1 << 9, + + // A replaced element that has replaced-element sizing + // characteristics (i.e., like images or iframes), as opposed to + // inline-block sizing characteristics (like form controls). + eReplacedSizing = 1 << 10, + + // Does this frame class support 'contain: layout' and + // 'contain:paint' (supporting one is equivalent to supporting the + // other). + eSupportsContainLayoutAndPaint = 1 << 11, + + // Does this frame class support `aspect-ratio` property. + eSupportsAspectRatio = 1 << 12, + + // These are to allow nsIFrame::Init to assert that IsFrameOfType + // implementations all call the base class method. They are only + // meaningful in DEBUG builds. + eDEBUGAllFrames = 1 << 30, + eDEBUGNoFrames = 1 << 31 + }; + + /** + * API for doing a quick check if a frame is of a given + * type. Returns true if the frame matches ALL flags passed in. + * + * Implementations should always override with inline virtual + * functions that call the base class's IsFrameOfType method. + */ + virtual bool IsFrameOfType(uint32_t aFlags) const { + return !(aFlags & ~( +#ifdef DEBUG + nsIFrame::eDEBUGAllFrames | +#endif + nsIFrame::eSupportsCSSTransforms | + nsIFrame::eSupportsContainLayoutAndPaint | + nsIFrame::eSupportsAspectRatio)); + } + + /** + * Return true if this frame's preferred size property or max size property + * contains a percentage value that should be resolved against zero when + * calculating its min-content contribution in the corresponding axis. + * + * This is a special case for webcompat required by CSS Sizing 3 §5.2.1c + * https://drafts.csswg.org/css-sizing-3/#replaced-percentage-min-contribution, + * and applies only to some replaced elements and form control elements. See + * CSS Sizing 3 §5.2.2 for the list of elements this rule applies to. + * https://drafts.csswg.org/css-sizing-3/#min-content-zero + * + * Bug 1463700: some callers may not match the spec by resolving the entire + * preferred size property or max size property against zero. + */ + bool IsPercentageResolvedAgainstZero( + const mozilla::StyleSize& aStyleSize, + const mozilla::StyleMaxSize& aStyleMaxSize) const; + + // Type of preferred size/min size/max size. + enum class SizeProperty { Size, MinSize, MaxSize }; + /** + * This is simliar to the above method but accepts LengthPercentage. Return + * true if the frame's preferred size property or max size property contains + * a percentage value that should be resolved against zero. For min size, it + * always returns true. + */ + bool IsPercentageResolvedAgainstZero(const mozilla::LengthPercentage& aSize, + SizeProperty aProperty) const; + + /** + * Returns true if the frame is a block wrapper. + */ + bool IsBlockWrapper() const; + + /** + * Returns true if the frame is an instance of nsBlockFrame or one of its + * subclasses. + */ + bool IsBlockFrameOrSubclass() const; + + /** + * Returns true if the frame is an instance of nsImageFrame or one of its + * subclasses. + */ + bool IsImageFrameOrSubclass() const; + + /** + * Get this frame's CSS containing block. + * + * The algorithm is defined in + * http://www.w3.org/TR/CSS2/visudet.html#containing-block-details. + * + * NOTE: This is guaranteed to return a non-null pointer when invoked on any + * frame other than the root frame. + * + * Requires SKIP_SCROLLED_FRAME to get behaviour matching the spec, otherwise + * it can return anonymous inner scrolled frames. Bug 1204044 is filed for + * investigating whether any of the callers actually require the default + * behaviour. + */ + enum { + // If the containing block is an anonymous scrolled frame, then skip over + // this and return the outer scroll frame. + SKIP_SCROLLED_FRAME = 0x01 + }; + nsIFrame* GetContainingBlock(uint32_t aFlags, + const nsStyleDisplay* aStyleDisplay) const; + nsIFrame* GetContainingBlock(uint32_t aFlags = 0) const { + return GetContainingBlock(aFlags, StyleDisplay()); + } + + /** + * If this frame can be a block container, i.e. whether it can serve as a + * containing block for its descendants. See also GetNearestBlockContainer() + * and GetContainingBlock(). + */ + bool IsBlockContainer() const; + + /** + * Is this frame a containing block for floating elements? + * Note that very few frames are, so default to false. + */ + virtual bool IsFloatContainingBlock() const { return false; } + + /** + * Is this a leaf frame? Frames that want the frame constructor to be able + * to construct kids for them should return false, all others should return + * true. Note that returning true here does not mean that the frame _can't_ + * have kids. It could still have kids created via + * nsIAnonymousContentCreator. Returning true indicates that "normal" + * (non-anonymous, CSS generated content, etc) children should not be + * constructed. + */ + bool IsLeaf() const { + MOZ_ASSERT(uint8_t(mClass) < mozilla::ArrayLength(sFrameClassBits)); + FrameClassBits bits = sFrameClassBits[uint8_t(mClass)]; + if (MOZ_UNLIKELY(bits & eFrameClassBitsDynamicLeaf)) { + return IsLeafDynamic(); + } + return bits & eFrameClassBitsLeaf; + } + + virtual bool IsLeafDynamic() const { return false; } + + /** + * Marks all display items created by this frame as needing a repaint, + * and calls SchedulePaint() if requested and one is not already pending. + * + * This includes all display items created by this frame, including + * container types. + * + * @param aDisplayItemKey If specified, only issues an invalidate + * if this frame painted a display item of that type during the + * previous paint. SVG rendering observers are always notified. + * @param aRebuildDisplayItems If true, then adds this frame to the + * list of modified frames for display list building. Only pass false + * if you're sure that the relevant display items will be rebuilt + * already (possibly by an ancestor being in the modified list). + */ + virtual void InvalidateFrame(uint32_t aDisplayItemKey = 0, + bool aRebuildDisplayItems = true); + + /** + * Same as InvalidateFrame(), but only mark a fixed rect as needing + * repainting. + * + * @param aRect The rect to invalidate, relative to the TopLeft of the + * frame's border box. + * @param aDisplayItemKey If specified, only issues an invalidate + * if this frame painted a display item of that type during the + * previous paint. SVG rendering observers are always notified. + * @param aRebuildDisplayItems If true, then adds this frame to the + * list of modified frames for display list building. Only pass false + * if you're sure that the relevant display items will be rebuilt + * already (possibly by an ancestor being in the modified list). + */ + virtual void InvalidateFrameWithRect(const nsRect& aRect, + uint32_t aDisplayItemKey = 0, + bool aRebuildDisplayItems = true); + + /** + * Calls InvalidateFrame() on all frames descendant frames (including + * this one). + * + * This function doesn't walk through placeholder frames to invalidate + * the out-of-flow frames. + * + * @param aRebuildDisplayItems If true, then adds this frame to the + * list of modified frames for display list building. Only pass false + * if you're sure that the relevant display items will be rebuilt + * already (possibly by an ancestor being in the modified list). + */ + void InvalidateFrameSubtree(bool aRebuildDisplayItems = true); + + /** + * Called when a frame is about to be removed and needs to be invalidated. + * Normally does nothing since DLBI handles removed frames. + */ + virtual void InvalidateFrameForRemoval() {} + + /** + * When HasUserData(frame->LayerIsPrerenderedDataKey()), then the + * entire overflow area of this frame has been rendered in its + * layer(s). + */ + static void* LayerIsPrerenderedDataKey() { + return &sLayerIsPrerenderedDataKey; + } + static uint8_t sLayerIsPrerenderedDataKey; + + /** + * Checks if a frame has had InvalidateFrame() called on it since the + * last paint. + * + * If true, then the invalid rect is returned in aRect, with an + * empty rect meaning all pixels drawn by this frame should be + * invalidated. + * If false, aRect is left unchanged. + */ + bool IsInvalid(nsRect& aRect); + + /** + * Check if any frame within the frame subtree (including this frame) + * returns true for IsInvalid(). + */ + bool HasInvalidFrameInSubtree() { + return HasAnyStateBits(NS_FRAME_NEEDS_PAINT | + NS_FRAME_DESCENDANT_NEEDS_PAINT); + } + + /** + * Removes the invalid state from the current frame and all + * descendant frames. + */ + void ClearInvalidationStateBits(); + + /** + * Ensures that the refresh driver is running, and schedules a view + * manager flush on the next tick. + * + * The view manager flush will update the layer tree, repaint any + * invalid areas in the layer tree and schedule a layer tree + * composite operation to display the layer tree. + * + * In general it is not necessary for frames to call this when they change. + * For example, changes that result in a reflow will have this called for + * them by PresContext::DoReflow when the reflow begins. Style changes that + * do not trigger a reflow should have this called for them by + * DoApplyRenderingChangeToTree. + * + * @param aType PAINT_COMPOSITE_ONLY : No changes have been made + * that require a layer tree update, so only schedule a layer + * tree composite. + */ + enum PaintType { PAINT_DEFAULT = 0, PAINT_COMPOSITE_ONLY }; + void SchedulePaint(PaintType aType = PAINT_DEFAULT, + bool aFrameChanged = true); + + // Similar to SchedulePaint() but without calling + // InvalidateRenderingObservers() for SVG. + void SchedulePaintWithoutInvalidatingObservers( + PaintType aType = PAINT_DEFAULT); + + /** + * Checks if the layer tree includes a dedicated layer for this + * frame/display item key pair, and invalidates at least aDamageRect + * area within that layer. + * + * If no layer is found, calls InvalidateFrame() instead. + * + * @param aDamageRect Area of the layer to invalidate. + * @param aFrameDamageRect If no layer is found, the area of the frame to + * invalidate. If null, the entire frame will be + * invalidated. + * @param aDisplayItemKey Display item type. + * @param aFlags UPDATE_IS_ASYNC : Will skip the invalidation + * if the found layer is being composited by a remote + * compositor. + * @return Layer, if found, nullptr otherwise. + */ + enum { UPDATE_IS_ASYNC = 1 << 0 }; + void InvalidateLayer(DisplayItemType aDisplayItemKey, + const nsIntRect* aDamageRect = nullptr, + const nsRect* aFrameDamageRect = nullptr, + uint32_t aFlags = 0); + + void MarkNeedsDisplayItemRebuild(); + + /** + * Returns a rect that encompasses everything that might be painted by + * this frame. This includes this frame, all its descendant frames, this + * frame's outline, and descendant frames' outline, but does not include + * areas clipped out by the CSS "overflow" and "clip" properties. + * + * HasOverflowAreas() (below) will return true when this overflow + * rect has been explicitly set, even if it matches mRect. + * XXX Note: because of a space optimization using the formula above, + * during reflow this function does not give accurate data if + * FinishAndStoreOverflow has been called but mRect hasn't yet been + * updated yet. FIXME: This actually isn't true, but it should be. + * + * The ink overflow rect should NEVER be used for things that + * affect layout. The scrollable overflow rect is permitted to affect + * layout. + * + * @return the rect relative to this frame's origin, but after + * CSS transforms have been applied (i.e. not really this frame's coordinate + * system, and may not contain the frame's border-box, e.g. if there + * is a CSS transform scaling it down) + */ + nsRect InkOverflowRect() const { + return GetOverflowRect(mozilla::OverflowType::Ink); + } + + /** + * Returns a rect that encompasses the area of this frame that the + * user should be able to scroll to reach. This is similar to + * InkOverflowRect, but does not include outline or shadows, and + * may in the future include more margins than ink overflow does. + * It does not include areas clipped out by the CSS "overflow" and + * "clip" properties. + * + * HasOverflowAreas() (below) will return true when this overflow + * rect has been explicitly set, even if it matches mRect. + * XXX Note: because of a space optimization using the formula above, + * during reflow this function does not give accurate data if + * FinishAndStoreOverflow has been called but mRect hasn't yet been + * updated yet. + * + * @return the rect relative to this frame's origin, but after + * CSS transforms have been applied (i.e. not really this frame's coordinate + * system, and may not contain the frame's border-box, e.g. if there + * is a CSS transform scaling it down) + */ + nsRect ScrollableOverflowRect() const { + return GetOverflowRect(mozilla::OverflowType::Scrollable); + } + + mozilla::OverflowAreas GetOverflowAreas() const; + + /** + * Same as GetOverflowAreas, except in this frame's coordinate + * system (before transforms are applied). + * + * @return the overflow areas relative to this frame, before any CSS + * transforms have been applied, i.e. in this frame's coordinate system + */ + mozilla::OverflowAreas GetOverflowAreasRelativeToSelf() const; + + /** + * Same as GetOverflowAreas, except relative to the parent frame. + * + * @return the overflow area relative to the parent frame, in the parent + * frame's coordinate system + */ + mozilla::OverflowAreas GetOverflowAreasRelativeToParent() const; + + /** + * Same as GetOverflowAreasRelativeToParent(), except that it also unions in + * the normal position overflow area if this frame is relatively or sticky + * positioned. + * + * @return the overflow area relative to the parent frame, in the parent + * frame's coordinate system + */ + mozilla::OverflowAreas GetActualAndNormalOverflowAreasRelativeToParent() + const; + + /** + * Same as ScrollableOverflowRect, except relative to the parent + * frame. + * + * @return the rect relative to the parent frame, in the parent frame's + * coordinate system + */ + nsRect ScrollableOverflowRectRelativeToParent() const; + + /** + * Same as ScrollableOverflowRect, except in this frame's coordinate + * system (before transforms are applied). + * + * @return the rect relative to this frame, before any CSS transforms have + * been applied, i.e. in this frame's coordinate system + */ + nsRect ScrollableOverflowRectRelativeToSelf() const; + + /** + * Like InkOverflowRect, except in this frame's + * coordinate system (before transforms are applied). + * + * @return the rect relative to this frame, before any CSS transforms have + * been applied, i.e. in this frame's coordinate system + */ + nsRect InkOverflowRectRelativeToSelf() const; + + /** + * Same as InkOverflowRect, except relative to the parent + * frame. + * + * @return the rect relative to the parent frame, in the parent frame's + * coordinate system + */ + nsRect InkOverflowRectRelativeToParent() const; + + /** + * Returns this frame's ink overflow rect as it would be before taking + * account of SVG effects or transforms. The rect returned is relative to + * this frame. + */ + nsRect PreEffectsInkOverflowRect() const; + + /** + * Store the overflow area in the frame's mOverflow.mInkOverflowDeltas + * fields or as a frame property in OverflowAreasProperty() so that it can + * be retrieved later without reflowing the frame. Returns true if either of + * the overflow areas changed. + */ + bool FinishAndStoreOverflow(mozilla::OverflowAreas& aOverflowAreas, + nsSize aNewSize, nsSize* aOldSize = nullptr, + const nsStyleDisplay* aStyleDisplay = nullptr); + + bool FinishAndStoreOverflow(ReflowOutput* aMetrics, + const nsStyleDisplay* aStyleDisplay = nullptr) { + return FinishAndStoreOverflow(aMetrics->mOverflowAreas, + nsSize(aMetrics->Width(), aMetrics->Height()), + nullptr, aStyleDisplay); + } + + /** + * Returns whether the frame has an overflow rect that is different from + * its border-box. + */ + bool HasOverflowAreas() const { + return mOverflow.mType != OverflowStorageType::None; + } + + /** + * Removes any stored overflow rects (visual and scrollable) from the frame. + * Returns true if the overflow changed. + */ + bool ClearOverflowRects(); + + /** + * Determine whether borders, padding, margins etc should NOT be applied + * on certain sides of the frame. + * @see mozilla::Sides in gfx/2d/BaseMargin.h + * @see mozilla::LogicalSides in layout/generic/WritingModes.h + * + * @note (See also bug 743402, comment 11) GetSkipSides() checks to see + * if this frame has a previous or next continuation to determine + * if a side should be skipped. + * So this only works after the entire frame tree has been reflowed. + * During reflow, if this frame can be split in the block axis, you + * should use nsSplittableFrame::PreReflowBlockLevelLogicalSkipSides(). + */ + Sides GetSkipSides() const; + virtual LogicalSides GetLogicalSkipSides() const { + return LogicalSides(mWritingMode); + } + + /** + * @returns true if this frame is selected. + */ + bool IsSelected() const { + return (GetContent() && GetContent()->IsMaybeSelected()) ? IsFrameSelected() + : false; + } + + /** + * Shouldn't be called if this is a `nsTextFrame`. Call the + * `nsTextFrame::SelectionStateChanged` overload instead. + */ + void SelectionStateChanged() { + MOZ_ASSERT(!IsTextFrame()); + InvalidateFrameSubtree(); // TODO: should this deal with continuations? + } + + /** + * Called to discover where this frame, or a parent frame has user-select + * style applied, which affects that way that it is selected. + * + * @param aSelectStyle out param. Returns the type of selection style found + * (using values defined in nsStyleConsts.h). + * + * @return Whether the frame can be selected (i.e. is not affected by + * user-select: none) + */ + bool IsSelectable(mozilla::StyleUserSelect* aSelectStyle) const; + + /** + * Returns whether this frame should have the content-block-size of a line, + * even if empty. + */ + bool ShouldHaveLineIfEmpty() const; + + /** + * Called to retrieve the SelectionController associated with the frame. + * + * @param aSelCon will contain the selection controller associated with + * the frame. + */ + nsresult GetSelectionController(nsPresContext* aPresContext, + nsISelectionController** aSelCon); + + /** + * Call to get nsFrameSelection for this frame. + */ + already_AddRefed<nsFrameSelection> GetFrameSelection(); + + /** + * GetConstFrameSelection returns an object which methods are safe to use for + * example in nsIFrame code. + */ + const nsFrameSelection* GetConstFrameSelection() const; + + /** + * called to find the previous/next character, word, or line. Returns the + * actual nsIFrame and the frame offset. THIS DOES NOT CHANGE SELECTION STATE. + * Uses frame's begin selection state to start. If no selection on this frame + * will return NS_ERROR_FAILURE. + * + * @param aPos is defined in nsFrameSelection + */ + virtual nsresult PeekOffset(mozilla::PeekOffsetStruct* aPos); + + private: + nsresult PeekOffsetForCharacter(mozilla::PeekOffsetStruct* aPos, + int32_t aOffset); + nsresult PeekOffsetForWord(mozilla::PeekOffsetStruct* aPos, int32_t aOffset); + nsresult PeekOffsetForLine(mozilla::PeekOffsetStruct* aPos); + nsresult PeekOffsetForLineEdge(mozilla::PeekOffsetStruct* aPos); + + /** + * Search for the first paragraph boundary before or after the given position + * @param aPos See description in nsFrameSelection.h. The following fields + * are used by this method: + * Input: mDirection + * Output: mResultContent, mContentOffset + */ + nsresult PeekOffsetForParagraph(mozilla::PeekOffsetStruct* aPos); + + public: + // given a frame five me the first/last leaf available + // XXX Robert O'Callahan wants to move these elsewhere + static void GetLastLeaf(nsIFrame** aFrame); + static void GetFirstLeaf(nsIFrame** aFrame); + + struct SelectablePeekReport { + /** the previous/next selectable leaf frame */ + nsIFrame* mFrame = nullptr; + /** + * 0 indicates that we arrived at the beginning of the output frame; -1 + * indicates that we arrived at its end. + */ + int32_t mOffset = 0; + /** whether the input frame and the returned frame are on different lines */ + bool mJumpedLine = false; + /** whether we met a hard break between the input and the returned frame */ + bool mJumpedHardBreak = false; + /** whether we jumped over a non-selectable frame during the search */ + bool mMovedOverNonSelectableText = false; + /** whether we met selectable text frame that isn't editable during the + * search */ + bool mHasSelectableFrame = false; + /** whether we ignored a br frame */ + bool mIgnoredBrFrame = false; + + FrameSearchResult PeekOffsetNoAmount(bool aForward) { + return mFrame->PeekOffsetNoAmount(aForward, &mOffset); + } + FrameSearchResult PeekOffsetCharacter(bool aForward, + PeekOffsetCharacterOptions aOptions) { + return mFrame->PeekOffsetCharacter(aForward, &mOffset, aOptions); + }; + + /** Transfers frame and offset info for PeekOffset() result */ + void TransferTo(mozilla::PeekOffsetStruct& aPos) const; + bool Failed() { return !mFrame; } + + explicit SelectablePeekReport(nsIFrame* aFrame = nullptr, + int32_t aOffset = 0) + : mFrame(aFrame), mOffset(aOffset) {} + MOZ_IMPLICIT SelectablePeekReport( + const mozilla::GenericErrorResult<nsresult>&& aErr); + }; + + /** + * Called to find the previous/next non-anonymous selectable leaf frame. + * + * @param aDirection the direction to move in (eDirPrevious or eDirNext) + * @param aOptions the other options which is same as + * PeekOffsetStruct::mOptions. + * FIXME: Due to the include hell, we cannot use the alias, PeekOffsetOptions + * is not available in this header file. + */ + SelectablePeekReport GetFrameFromDirection( + nsDirection aDirection, + const mozilla::EnumSet<mozilla::PeekOffsetOption>& aOptions); + SelectablePeekReport GetFrameFromDirection( + const mozilla::PeekOffsetStruct& aPos); + + /** + * Return: + * (1) the containing block frame for a line; i.e. the frame which + * supports a line iterator, or null if none can be found; and + * (2) the frame to use to get a line number, which will be direct child of + * the returned containing block. + * @param aLockScroll true to avoid breaking outside scrollframes. + */ + std::pair<nsIFrame*, nsIFrame*> GetContainingBlockForLine( + bool aLockScroll) const; + + private: + Result<bool, nsresult> IsVisuallyAtLineEdge(nsILineIterator* aLineIterator, + int32_t aLine, + nsDirection aDirection); + Result<bool, nsresult> IsLogicallyAtLineEdge(nsILineIterator* aLineIterator, + int32_t aLine, + nsDirection aDirection); + + public: + /** + * Called to tell a frame that one of its child frames is dirty (i.e., + * has the NS_FRAME_IS_DIRTY *or* NS_FRAME_HAS_DIRTY_CHILDREN bit + * set). This should always set the NS_FRAME_HAS_DIRTY_CHILDREN on + * the frame, and may do other work. + */ + virtual void ChildIsDirty(nsIFrame* aChild); + + /** + * Called to retrieve this frame's accessible. + * If this frame implements Accessibility return a valid accessible + * If not return NS_ERROR_NOT_IMPLEMENTED. + * Note: LocalAccessible must be refcountable. Do not implement directly on + * your frame Use a mediatior of some kind. + */ +#ifdef ACCESSIBILITY + virtual mozilla::a11y::AccType AccessibleType(); +#endif + + /** + * Get the frame whose style should be the parent of this frame's style (i.e., + * provide the parent style). + * + * This frame must either be an ancestor of this frame or a child. If + * this returns a child frame, then the child frame must be sure to + * return a grandparent or higher! Furthermore, if a child frame is + * returned it must have the same GetContent() as this frame. + * + * @param aProviderFrame (out) the frame associated with the returned value + * or nullptr if the style is for display:contents content. + * @return The style that should be the parent of this frame's style. Null is + * permitted, and means that this frame's style should be the root of + * the style tree. + */ + virtual ComputedStyle* GetParentComputedStyle( + nsIFrame** aProviderFrame) const { + return DoGetParentComputedStyle(aProviderFrame); + } + + /** + * Do the work for getting the parent ComputedStyle frame so that + * other frame's |GetParentComputedStyle| methods can call this + * method on *another* frame. (This function handles out-of-flow + * frames by using the frame manager's placeholder map and it also + * handles block-within-inline and generated content wrappers.) + * + * @param aProviderFrame (out) the frame associated with the returned value + * or null if the ComputedStyle is for display:contents content. + * @return The ComputedStyle that should be the parent of this frame's + * ComputedStyle. Null is permitted, and means that this frame's + * ComputedStyle should be the root of the ComputedStyle tree. + */ + ComputedStyle* DoGetParentComputedStyle(nsIFrame** aProviderFrame) const; + + /** + * Adjust the given parent frame to the right ComputedStyle parent frame for + * the child, given the pseudo-type of the prospective child. This handles + * things like walking out of table pseudos and so forth. + * + * @param aProspectiveParent what GetParent() on the child returns. + * Must not be null. + * @param aChildPseudo the child's pseudo type, if any. + */ + static nsIFrame* CorrectStyleParentFrame( + nsIFrame* aProspectiveParent, mozilla::PseudoStyleType aChildPseudo); + + /** + * Called by RestyleManager to update the style of anonymous boxes + * directly associated with this frame. + * + * The passed-in ServoRestyleState can be used to create new ComputedStyles as + * needed, as well as posting changes to the change list. + * + * It's guaranteed to already have a change in it for this frame and this + * frame's content. + * + * This function will be called after this frame's style has already been + * updated. This function will only be called on frames which have the + * NS_FRAME_OWNS_ANON_BOXES bit set. + */ + void UpdateStyleOfOwnedAnonBoxes(mozilla::ServoRestyleState& aRestyleState) { + if (HasAnyStateBits(NS_FRAME_OWNS_ANON_BOXES)) { + DoUpdateStyleOfOwnedAnonBoxes(aRestyleState); + } + } + + mozilla::ContainSizeAxes GetContainSizeAxes() const { + return StyleDisplay()->GetContainSizeAxes(*this); + } + + Maybe<nscoord> ContainIntrinsicBSize(nscoord aNoneValue = 0) const { + return GetContainSizeAxes().ContainIntrinsicBSize(*this, aNoneValue); + } + + Maybe<nscoord> ContainIntrinsicISize(nscoord aNoneValue = 0) const { + return GetContainSizeAxes().ContainIntrinsicISize(*this, aNoneValue); + } + + protected: + // This does the actual work of UpdateStyleOfOwnedAnonBoxes. It calls + // AppendDirectlyOwnedAnonBoxes to find all of the anonymous boxes + // owned by this frame, and then updates styles on each of them. + void DoUpdateStyleOfOwnedAnonBoxes(mozilla::ServoRestyleState& aRestyleState); + + // A helper for DoUpdateStyleOfOwnedAnonBoxes for the specific case + // of the owned anon box being a child of this frame. + void UpdateStyleOfChildAnonBox(nsIFrame* aChildFrame, + mozilla::ServoRestyleState& aRestyleState); + + // Allow ServoRestyleState to call UpdateStyleOfChildAnonBox. + friend class mozilla::ServoRestyleState; + + public: + // A helper both for UpdateStyleOfChildAnonBox, and to update frame-backed + // pseudo-elements in RestyleManager. + // + // This gets a ComputedStyle that will be the new style for `aChildFrame`, and + // takes care of updating it, calling CalcStyleDifference, and adding to the + // change list as appropriate. + // + // If aContinuationComputedStyle is not Nothing, it should be used for + // continuations instead of aNewComputedStyle. In either case, changehints + // are only computed based on aNewComputedStyle. + // + // Returns the generated change hint for the frame. + static nsChangeHint UpdateStyleOfOwnedChildFrame( + nsIFrame* aChildFrame, ComputedStyle* aNewComputedStyle, + mozilla::ServoRestyleState& aRestyleState, + const Maybe<ComputedStyle*>& aContinuationComputedStyle = Nothing()); + + struct OwnedAnonBox { + typedef void (*UpdateStyleFn)(nsIFrame* aOwningFrame, nsIFrame* aAnonBox, + mozilla::ServoRestyleState& aRestyleState); + + explicit OwnedAnonBox(nsIFrame* aAnonBoxFrame, + UpdateStyleFn aUpdateStyleFn = nullptr) + : mAnonBoxFrame(aAnonBoxFrame), mUpdateStyleFn(aUpdateStyleFn) {} + + nsIFrame* mAnonBoxFrame; + UpdateStyleFn mUpdateStyleFn; + }; + + /** + * Appends information about all of the anonymous boxes owned by this frame, + * including other anonymous boxes owned by those which this frame owns + * directly. + */ + void AppendOwnedAnonBoxes(nsTArray<OwnedAnonBox>& aResult) { + if (HasAnyStateBits(NS_FRAME_OWNS_ANON_BOXES)) { + if (IsInlineFrame()) { + // See comment in nsIFrame::DoUpdateStyleOfOwnedAnonBoxes for why + // we skip nsInlineFrames. + return; + } + DoAppendOwnedAnonBoxes(aResult); + } + } + + protected: + // This does the actual work of AppendOwnedAnonBoxes. + void DoAppendOwnedAnonBoxes(nsTArray<OwnedAnonBox>& aResult); + + public: + /** + * Hook subclasses can override to return their owned anonymous boxes. + * + * This function only appends anonymous boxes that are directly owned by + * this frame, i.e. direct children or (for certain frames) a wrapper + * parent, unlike AppendOwnedAnonBoxes, which will append all anonymous + * boxes transitively owned by this frame. + */ + virtual void AppendDirectlyOwnedAnonBoxes(nsTArray<OwnedAnonBox>& aResult); + + /** + * Determines whether a frame is visible for painting; + * taking into account whether it is painting a selection or printing. + */ + bool IsVisibleForPainting() const; + /** + * Determines whether a frame is visible for painting or collapsed; + * taking into account whether it is painting a selection or printing, + */ + bool IsVisibleOrCollapsedForPainting() const; + + /** + * Determines if this frame is a stacking context. + */ + bool IsStackingContext(const nsStyleDisplay*, const nsStyleEffects*); + bool IsStackingContext(); + + // Whether we should paint backgrounds or not. + struct ShouldPaintBackground { + bool mColor = false; + bool mImage = false; + }; + ShouldPaintBackground ComputeShouldPaintBackground() const; + + /** + * Determine whether the frame is logically empty, which is roughly + * whether the layout would be the same whether or not the frame is + * present. Placeholder frames should return true. Block frames + * should be considered empty whenever margins collapse through them, + * even though those margins are relevant. Text frames containing + * only whitespace that does not contribute to the height of the line + * should return true. + */ + virtual bool IsEmpty(); + /** + * Return the same as IsEmpty(). This may only be called after the frame + * has been reflowed and before any further style or content changes. + */ + virtual bool CachedIsEmpty(); + /** + * Determine whether the frame is logically empty, assuming that all + * its children are empty. + */ + virtual bool IsSelfEmpty(); + + /** + * IsGeneratedContentFrame returns whether a frame corresponds to + * generated content + * + * @return whether the frame correspods to generated content + */ + bool IsGeneratedContentFrame() const { + return HasAnyStateBits(NS_FRAME_GENERATED_CONTENT); + } + + /** + * IsPseudoFrame returns whether a frame is a pseudo frame (eg an + * anonymous table-row frame created for a CSS table-cell without an + * enclosing table-row. + * + * @param aParentContent the content node corresponding to the parent frame + * @return whether the frame is a pseudo frame + */ + bool IsPseudoFrame(const nsIContent* aParentContent) { + return mContent == aParentContent; + } + + /** + * Support for reading and writing properties on the frame. + * These call through to the frame's FrameProperties object, if it + * exists, but avoid creating it if no property is ever set. + */ + template <typename T> + FrameProperties::PropertyType<T> GetProperty( + FrameProperties::Descriptor<T> aProperty, + bool* aFoundResult = nullptr) const { + return mProperties.Get(aProperty, aFoundResult); + } + + template <typename T> + bool HasProperty(FrameProperties::Descriptor<T> aProperty) const { + return mProperties.Has(aProperty); + } + + /** + * Add a property, or update an existing property for the given descriptor. + * + * Note: This function asserts if updating an existing nsFrameList property. + */ + template <typename T> + void SetProperty(FrameProperties::Descriptor<T> aProperty, + FrameProperties::PropertyType<T> aValue) { + if constexpr (std::is_same_v<T, nsFrameList>) { + MOZ_ASSERT(aValue, "Shouldn't set nullptr to a nsFrameList property!"); + MOZ_ASSERT(!HasProperty(aProperty), + "Shouldn't update an existing nsFrameList property!"); + } + mProperties.Set(aProperty, aValue, this); + } + + // Unconditionally add a property; use ONLY if the descriptor is known + // to NOT already be present. + template <typename T> + void AddProperty(FrameProperties::Descriptor<T> aProperty, + FrameProperties::PropertyType<T> aValue) { + mProperties.Add(aProperty, aValue); + } + + /** + * Remove a property and return its value without destroying it. May return + * nullptr. + * + * Note: The caller is responsible for handling the life cycle of the returned + * value. + */ + template <typename T> + [[nodiscard]] FrameProperties::PropertyType<T> TakeProperty( + FrameProperties::Descriptor<T> aProperty, bool* aFoundResult = nullptr) { + return mProperties.Take(aProperty, aFoundResult); + } + + template <typename T> + void RemoveProperty(FrameProperties::Descriptor<T> aProperty) { + mProperties.Remove(aProperty, this); + } + + void RemoveAllProperties() { mProperties.RemoveAll(this); } + + // nsIFrames themselves are in the nsPresArena, and so are not measured here. + // Instead, this measures heap-allocated things hanging off the nsIFrame, and + // likewise for its descendants. + virtual void AddSizeOfExcludingThisForTree(nsWindowSizes& aWindowSizes) const; + + /** + * Return true if and only if this frame obeys visibility:hidden. + * if it does not, then nsContainerFrame will hide its view even though + * this means children can't be made visible again. + */ + virtual bool SupportsVisibilityHidden() { return true; } + + /** + * Returns the clip rect set via the 'clip' property, if the 'clip' property + * applies to this frame; otherwise returns Nothing(). The 'clip' property + * applies to HTML frames if they are absolutely positioned. The 'clip' + * property applies to SVG frames regardless of the value of the 'position' + * property. + * + * The coordinates of the returned rectangle are relative to this frame's + * origin. + */ + Maybe<nsRect> GetClipPropClipRect(const nsStyleDisplay* aDisp, + const nsStyleEffects* aEffects, + const nsSize& aSize) const; + + struct Focusable { + bool mFocusable = false; + // The computed tab index: + // < 0 if not tabbable + // == 0 if in normal tab order + // > 0 can be tabbed to in the order specified by this value + int32_t mTabIndex = -1; + + explicit operator bool() const { return mFocusable; } + }; + + /** + * Check if this frame is focusable and in the current tab order. + * Tabbable is indicated by a nonnegative tabindex & is a subset of focusable. + * For example, only the selected radio button in a group is in the + * tab order, unless the radio group has no selection in which case + * all of the visible, non-disabled radio buttons in the group are + * in the tab order. On the other hand, all of the visible, non-disabled + * radio buttons are always focusable via clicking or script. + * Also, depending on the pref accessibility.tabfocus some widgets may be + * focusable but removed from the tab order. This is the default on + * Mac OS X, where fewer items are focusable. + * @param [in, optional] aWithMouse, is this focus query for mouse clicking + * @param [in, optional] aCheckVisibility, whether to treat an invisible + * frame as not focusable + * @return whether the frame is focusable via mouse, kbd or script. + */ + [[nodiscard]] Focusable IsFocusable(bool aWithMouse = false, + bool aCheckVisibility = true); + + protected: + // Helper for IsFocusable. + bool IsFocusableDueToScrollFrame(); + + /** + * Returns true if this box clips its children, e.g., if this box is an + * scrollbox or has overflow: clip in both axes. + */ + bool DoesClipChildrenInBothAxes() const; + + /** + * NOTE: aStatus is assumed to be already-initialized. The reflow statuses of + * any reflowed absolute children will be merged into aStatus; aside from + * that, this method won't modify aStatus. + */ + void ReflowAbsoluteFrames(nsPresContext* aPresContext, + ReflowOutput& aDesiredSize, + const ReflowInput& aReflowInput, + nsReflowStatus& aStatus, + bool aConstrainBSize = true); + + private: + Maybe<nscoord> ComputeInlineSizeFromAspectRatio( + mozilla::WritingMode aWM, const mozilla::LogicalSize& aCBSize, + const mozilla::LogicalSize& aContentEdgeToBoxSizing, + const mozilla::StyleSizeOverrides& aSizeOverrides, + mozilla::ComputeSizeFlags aFlags) const; + + public: + /** + * @return true if this text frame ends with a newline character. It + * should return false if this is not a text frame. + */ + virtual bool HasSignificantTerminalNewline() const; + + struct CaretPosition { + CaretPosition(); + ~CaretPosition(); + + nsCOMPtr<nsIContent> mResultContent; + int32_t mContentOffset; + }; + + /** + * gets the first or last possible caret position within the frame + * + * @param [in] aStart + * true for getting the first possible caret position + * false for getting the last possible caret position + * @return The caret position in a CaretPosition. + * the returned value is a 'best effort' in case errors + * are encountered rummaging through the frame. + */ + CaretPosition GetExtremeCaretPosition(bool aStart); + + /** + * Query whether this frame supports getting a line iterator. + * @return true if a line iterator is supported. + */ + virtual bool CanProvideLineIterator() const { return false; } + + /** + * Get a line iterator for this frame, if supported. + * + * @return nullptr if no line iterator is supported. + * @note dispose the line iterator using nsILineIterator::DisposeLineIterator + */ + virtual nsILineIterator* GetLineIterator() { return nullptr; } + + /** + * If this frame is a next-in-flow, and its prev-in-flow has something on its + * overflow list, pull those frames into the child list of this one. + */ + virtual void PullOverflowsFromPrevInFlow() {} + + /** + * Accessors for the absolute containing block. + */ + bool IsAbsoluteContainer() const { + return !!(mState & NS_FRAME_HAS_ABSPOS_CHILDREN); + } + bool HasAbsolutelyPositionedChildren() const; + nsAbsoluteContainingBlock* GetAbsoluteContainingBlock() const; + void MarkAsAbsoluteContainingBlock(); + void MarkAsNotAbsoluteContainingBlock(); + // Child frame types override this function to select their own child list + // name + virtual mozilla::FrameChildListID GetAbsoluteListID() const { + return mozilla::FrameChildListID::Absolute; + } + + // Checks if we (or any of our descendants) have NS_FRAME_PAINTED_THEBES set, + // and clears this bit if so. + bool CheckAndClearPaintedState(); + + // Checks if we (or any of our descendents) have mBuiltDisplayList set, and + // clears this bit if so. + bool CheckAndClearDisplayListState(); + + // CSS visibility just doesn't cut it because it doesn't inherit through + // documents. Also if this frame is in a hidden card of a deck then it isn't + // visible either and that isn't expressed using CSS visibility. Also if it + // is in a hidden view (there are a few cases left and they are hopefully + // going away soon). + // If the VISIBILITY_CROSS_CHROME_CONTENT_BOUNDARY flag is passed then we + // ignore the chrome/content boundary, otherwise we stop looking when we + // reach it. + enum { VISIBILITY_CROSS_CHROME_CONTENT_BOUNDARY = 0x01 }; + bool IsVisibleConsideringAncestors(uint32_t aFlags = 0) const; + + struct FrameWithDistance { + nsIFrame* mFrame; + nscoord mXDistance; + nscoord mYDistance; + }; + + /** + * Finds a frame that is closer to a specified point than a current + * distance. Distance is measured as for text selection -- a closer x + * distance beats a closer y distance. + * + * Normally, this function will only check the distance between this + * frame's rectangle and the specified point. SVGTextFrame overrides + * this so that it can manage all of its descendant frames and take + * into account any SVG text layout. + * + * If aPoint is closer to this frame's rectangle than aCurrentBestFrame + * indicates, then aCurrentBestFrame is updated with the distance between + * aPoint and this frame's rectangle, and with a pointer to this frame. + * If aPoint is not closer, then aCurrentBestFrame is left unchanged. + * + * @param aPoint The point to check for its distance to this frame. + * @param aCurrentBestFrame Pointer to a struct that will be updated with + * a pointer to this frame and its distance to aPoint, if this frame + * is indeed closer than the current distance in aCurrentBestFrame. + */ + virtual void FindCloserFrameForSelection( + const nsPoint& aPoint, FrameWithDistance* aCurrentBestFrame); + + /** + * Is this a flex item? (i.e. a non-abs-pos child of a flex container) + */ + inline bool IsFlexItem() const; + /** + * Is this a grid item? (i.e. a non-abs-pos child of a grid container) + */ + inline bool IsGridItem() const; + /** + * Is this a flex or grid item? (i.e. a non-abs-pos child of a flex/grid + * container) + */ + inline bool IsFlexOrGridItem() const; + inline bool IsFlexOrGridContainer() const; + + /** + * Return true if this frame has masonry layout in aAxis. + * @note only valid to call on nsGridContainerFrames + */ + inline bool IsMasonry(mozilla::LogicalAxis aAxis) const; + + /** + * @return true if this frame is used as a table caption. + */ + inline bool IsTableCaption() const; + + inline bool IsBlockOutside() const; + inline bool IsInlineOutside() const; + inline mozilla::StyleDisplay GetDisplay() const; + inline bool IsFloating() const; + inline bool IsAbsPosContainingBlock() const; + inline bool IsFixedPosContainingBlock() const; + inline bool IsRelativelyOrStickyPositioned() const; + + // Note: In general, you'd want to call IsRelativelyOrStickyPositioned() + // unless you want to deal with "position:relative" and "position:sticky" + // differently. + inline bool IsRelativelyPositioned() const; + inline bool IsStickyPositioned() const; + + inline bool IsAbsolutelyPositioned( + const nsStyleDisplay* aStyleDisplay = nullptr) const; + inline bool IsTrueOverflowContainer() const; + + // Does this frame have "column-span: all" style. + // + // Note this only checks computed style, but not testing whether the + // containing block formatting context was established by a multicol. Callers + // need to use IsColumnSpanInMulticolSubtree() to check whether multi-column + // effects apply or not. + inline bool IsColumnSpan() const; + + // Like IsColumnSpan(), but this also checks whether the frame has a + // multi-column ancestor or not. + inline bool IsColumnSpanInMulticolSubtree() const; + + /** + * Returns the vertical-align value to be used for layout, if it is one + * of the enumerated values. If this is an SVG text frame, it returns a value + * that corresponds to the value of dominant-baseline. If the + * vertical-align property has length or percentage value, this returns + * Nothing(). + */ + Maybe<mozilla::StyleVerticalAlignKeyword> VerticalAlignEnum() const; + + /** + * Adds the NS_FRAME_IN_POPUP state bit to aFrame, and + * all descendant frames (including cross-doc ones). + */ + static void AddInPopupStateBitToDescendants(nsIFrame* aFrame); + /** + * Removes the NS_FRAME_IN_POPUP state bit from aFrame and + * all descendant frames (including cross-doc ones), unless + * the frame is a popup itself. + */ + static void RemoveInPopupStateBitFromDescendants(nsIFrame* aFrame); + + /** + * Return true if aFrame is in an {ib} split and is NOT one of the + * continuations of the first inline in it. + */ + bool FrameIsNonFirstInIBSplit() const { + return HasAnyStateBits(NS_FRAME_PART_OF_IBSPLIT) && + FirstContinuation()->GetProperty(nsIFrame::IBSplitPrevSibling()); + } + + /** + * Return true if aFrame is in an {ib} split and is NOT one of the + * continuations of the last inline in it. + */ + bool FrameIsNonLastInIBSplit() const { + return HasAnyStateBits(NS_FRAME_PART_OF_IBSPLIT) && + FirstContinuation()->GetProperty(nsIFrame::IBSplitSibling()); + } + + /** + * Return whether this is a frame whose width is used when computing + * the font size inflation of its descendants. + */ + bool IsContainerForFontSizeInflation() const { + return HasAnyStateBits(NS_FRAME_FONT_INFLATION_CONTAINER); + } + + /** + * Return whether this frame or any of its children is dirty. + */ + bool IsSubtreeDirty() const { + return HasAnyStateBits(NS_FRAME_IS_DIRTY | NS_FRAME_HAS_DIRTY_CHILDREN); + } + + /** + * Returns true if the frame is an SVGTextFrame or one of its descendants. + */ + bool IsInSVGTextSubtree() const { + return HasAnyStateBits(NS_FRAME_IS_SVG_TEXT); + } + + /** + * Return whether this frame keeps track of overflow areas. (Frames for + * non-display SVG elements -- e.g. <clipPath> -- do not maintain overflow + * areas, because they're never painted.) + */ + bool FrameMaintainsOverflow() const { + return !HasAllStateBits(NS_FRAME_SVG_LAYOUT | NS_FRAME_IS_NONDISPLAY) && + !(IsSVGOuterSVGFrame() && HasAnyStateBits(NS_FRAME_IS_NONDISPLAY)); + } + + /* + * @param aStyleDisplay: If the caller has this->StyleDisplay(), providing + * it here will improve performance. + */ + bool BackfaceIsHidden(const nsStyleDisplay* aStyleDisplay) const { + MOZ_ASSERT(aStyleDisplay == StyleDisplay()); + return aStyleDisplay->BackfaceIsHidden(); + } + bool BackfaceIsHidden() const { return StyleDisplay()->BackfaceIsHidden(); } + + /** + * Returns true if the frame is scrolled out of view. + */ + bool IsScrolledOutOfView() const; + + /** + * Computes a 2D matrix from the -moz-window-transform and + * -moz-window-transform-origin properties on aFrame. + * Values that don't result in a 2D matrix will be ignored and an identity + * matrix will be returned instead. + */ + Matrix ComputeWidgetTransform() const; + + /** + * @return true iff this frame has one or more associated image requests. + * @see mozilla::css::ImageLoader. + */ + bool HasImageRequest() const { return mHasImageRequest; } + + /** + * Update this frame's image request state. + */ + void SetHasImageRequest(bool aHasRequest) { mHasImageRequest = aHasRequest; } + + /** + * Whether this frame has a first-letter child. If it does, the frame is + * actually an nsContainerFrame and the first-letter frame can be gotten by + * walking up to the nearest ancestor blockframe and getting its first + * continuation's nsContainerFrame::FirstLetterProperty() property. This will + * only return true for the first continuation of the first-letter's parent. + */ + bool HasFirstLetterChild() const { return mHasFirstLetterChild; } + + /** + * Whether this frame's parent is a wrapper anonymous box. See documentation + * for mParentIsWrapperAnonBox. + */ + bool ParentIsWrapperAnonBox() const { return mParentIsWrapperAnonBox; } + void SetParentIsWrapperAnonBox() { mParentIsWrapperAnonBox = true; } + + /** + * Whether this is a wrapper anonymous box needing a restyle. + */ + bool IsWrapperAnonBoxNeedingRestyle() const { + return mIsWrapperBoxNeedingRestyle; + } + void SetIsWrapperAnonBoxNeedingRestyle(bool aNeedsRestyle) { + mIsWrapperBoxNeedingRestyle = aNeedsRestyle; + } + + bool MayHaveTransformAnimation() const { return mMayHaveTransformAnimation; } + void SetMayHaveTransformAnimation() { + AddStateBits(NS_FRAME_MAY_BE_TRANSFORMED); + mMayHaveTransformAnimation = true; + } + bool MayHaveOpacityAnimation() const { return mMayHaveOpacityAnimation; } + void SetMayHaveOpacityAnimation() { mMayHaveOpacityAnimation = true; } + + // Returns true if this frame is visible or may have visible descendants. + // Note: This function is accurate only on primary frames, because + // mAllDescendantsAreInvisible is not updated on continuations. + bool IsVisibleOrMayHaveVisibleDescendants() const { + return !mAllDescendantsAreInvisible || StyleVisibility()->IsVisible(); + } + // Update mAllDescendantsAreInvisible flag for this frame and ancestors. + void UpdateVisibleDescendantsState(); + + void UpdateAnimationVisibility(); + + /** + * If this returns true, the frame it's called on should get the + * NS_FRAME_HAS_DIRTY_CHILDREN bit set on it by the caller; either directly + * if it's already in reflow, or via calling FrameNeedsReflow() to schedule a + * reflow. + */ + virtual bool RenumberFrameAndDescendants(int32_t* aOrdinal, int32_t aDepth, + int32_t aIncrement, + bool aForCounting) { + return false; + } + + enum class ExtremumLength { + MinContent, + MaxContent, + MozAvailable, + FitContent, + FitContentFunction, + }; + + template <typename SizeOrMaxSize> + static Maybe<ExtremumLength> ToExtremumLength(const SizeOrMaxSize& aSize) { + switch (aSize.tag) { + case SizeOrMaxSize::Tag::MinContent: + return mozilla::Some(ExtremumLength::MinContent); + case SizeOrMaxSize::Tag::MaxContent: + return mozilla::Some(ExtremumLength::MaxContent); + case SizeOrMaxSize::Tag::MozAvailable: + return mozilla::Some(ExtremumLength::MozAvailable); + case SizeOrMaxSize::Tag::FitContent: + return mozilla::Some(ExtremumLength::FitContent); + case SizeOrMaxSize::Tag::FitContentFunction: + return mozilla::Some(ExtremumLength::FitContentFunction); + default: + return mozilla::Nothing(); + } + } + + /** + * Helper function - computes the content-box inline size for aSize, which is + * a more complex version to resolve a StyleExtremumLength. + * @param aAvailableISizeOverride If this has a value, it is used as the + * available inline-size instead of + * aContainingBlockSize.ISize(aWM) when + * resolving fit-content. + */ + struct ISizeComputationResult { + nscoord mISize = 0; + AspectRatioUsage mAspectRatioUsage = AspectRatioUsage::None; + }; + ISizeComputationResult ComputeISizeValue( + gfxContext* aRenderingContext, const mozilla::WritingMode aWM, + const mozilla::LogicalSize& aContainingBlockSize, + const mozilla::LogicalSize& aContentEdgeToBoxSizing, + nscoord aBoxSizingToMarginEdge, ExtremumLength aSize, + Maybe<nscoord> aAvailableISizeOverride, + const mozilla::StyleSizeOverrides& aSizeOverrides, + mozilla::ComputeSizeFlags aFlags); + + /** + * Helper function - computes the content-box inline size for aSize, which is + * a simpler version to resolve a LengthPercentage. + */ + nscoord ComputeISizeValue(const mozilla::WritingMode aWM, + const mozilla::LogicalSize& aContainingBlockSize, + const mozilla::LogicalSize& aContentEdgeToBoxSizing, + const LengthPercentage& aSize); + + template <typename SizeOrMaxSize> + ISizeComputationResult ComputeISizeValue( + gfxContext* aRenderingContext, const mozilla::WritingMode aWM, + const mozilla::LogicalSize& aContainingBlockSize, + const mozilla::LogicalSize& aContentEdgeToBoxSizing, + nscoord aBoxSizingToMarginEdge, const SizeOrMaxSize& aSize, + const mozilla::StyleSizeOverrides& aSizeOverrides = {}, + mozilla::ComputeSizeFlags aFlags = {}) { + if (aSize.IsLengthPercentage()) { + return {ComputeISizeValue(aWM, aContainingBlockSize, + aContentEdgeToBoxSizing, + aSize.AsLengthPercentage())}; + } + auto length = ToExtremumLength(aSize); + MOZ_ASSERT(length, "This doesn't handle none / auto"); + Maybe<nscoord> availbleISizeOverride; + if (aSize.IsFitContentFunction()) { + availbleISizeOverride.emplace(aSize.AsFitContentFunction().Resolve( + aContainingBlockSize.ISize(aWM))); + } + return ComputeISizeValue(aRenderingContext, aWM, aContainingBlockSize, + aContentEdgeToBoxSizing, aBoxSizingToMarginEdge, + length.valueOr(ExtremumLength::MinContent), + availbleISizeOverride, aSizeOverrides, aFlags); + } + + DisplayItemArray& DisplayItems() { return mDisplayItems; } + const DisplayItemArray& DisplayItems() const { return mDisplayItems; } + + void AddDisplayItem(nsDisplayItem* aItem); + bool RemoveDisplayItem(nsDisplayItem* aItem); + void RemoveDisplayItemDataForDeletion(); + bool HasDisplayItems(); + bool HasDisplayItem(nsDisplayItem* aItem); + bool HasDisplayItem(uint32_t aKey); + + static void PrintDisplayList(nsDisplayListBuilder* aBuilder, + const nsDisplayList& aList, + bool aDumpHtml = false); + static void PrintDisplayList(nsDisplayListBuilder* aBuilder, + const nsDisplayList& aList, + std::stringstream& aStream, + bool aDumpHtml = false); + static void PrintDisplayItem(nsDisplayListBuilder* aBuilder, + nsDisplayItem* aItem, std::stringstream& aStream, + uint32_t aIndent = 0, bool aDumpSublist = false, + bool aDumpHtml = false); +#ifdef MOZ_DUMP_PAINTING + static void PrintDisplayListSet(nsDisplayListBuilder* aBuilder, + const nsDisplayListSet& aSet, + std::stringstream& aStream, + bool aDumpHtml = false); +#endif + + /** + * Adds display items for standard CSS background if necessary. + * Does not check IsVisibleForPainting. + * @return whether a themed background item was created. + */ + bool DisplayBackgroundUnconditional(nsDisplayListBuilder* aBuilder, + const nsDisplayListSet& aLists); + /** + * Adds display items for standard CSS borders, background and outline for + * for this frame, as necessary. Checks IsVisibleForPainting and won't + * display anything if the frame is not visible. + */ + void DisplayBorderBackgroundOutline(nsDisplayListBuilder* aBuilder, + const nsDisplayListSet& aLists); + /** + * Add a display item for the CSS outline. Does not check visibility. + */ + void DisplayOutlineUnconditional(nsDisplayListBuilder* aBuilder, + const nsDisplayListSet& aLists); + /** + * Add a display item for the CSS outline, after calling + * IsVisibleForPainting to confirm we are visible. + */ + void DisplayOutline(nsDisplayListBuilder* aBuilder, + const nsDisplayListSet& aLists); + + /** + * Add a display item for CSS inset box shadows. Does not check visibility. + */ + void DisplayInsetBoxShadowUnconditional(nsDisplayListBuilder* aBuilder, + nsDisplayList* aList); + + /** + * Add a display item for CSS inset box shadow, after calling + * IsVisibleForPainting to confirm we are visible. + */ + void DisplayInsetBoxShadow(nsDisplayListBuilder* aBuilder, + nsDisplayList* aList); + + /** + * Add a display item for CSS outset box shadows. Does not check visibility. + */ + void DisplayOutsetBoxShadowUnconditional(nsDisplayListBuilder* aBuilder, + nsDisplayList* aList); + + /** + * Add a display item for CSS outset box shadow, after calling + * IsVisibleForPainting to confirm we are visible. + */ + void DisplayOutsetBoxShadow(nsDisplayListBuilder* aBuilder, + nsDisplayList* aList); + + bool ForceDescendIntoIfVisible() const { return mForceDescendIntoIfVisible; } + void SetForceDescendIntoIfVisible(bool aForce) { + mForceDescendIntoIfVisible = aForce; + } + + bool BuiltDisplayList() const { return mBuiltDisplayList; } + void SetBuiltDisplayList(const bool aBuilt) { mBuiltDisplayList = aBuilt; } + + bool IsFrameModified() const { return mFrameIsModified; } + void SetFrameIsModified(const bool aFrameIsModified) { + mFrameIsModified = aFrameIsModified; + } + + bool HasModifiedDescendants() const { return mHasModifiedDescendants; } + void SetHasModifiedDescendants(const bool aHasModifiedDescendants) { + mHasModifiedDescendants = aHasModifiedDescendants; + } + + bool HasOverrideDirtyRegion() const { return mHasOverrideDirtyRegion; } + void SetHasOverrideDirtyRegion(const bool aHasDirtyRegion) { + mHasOverrideDirtyRegion = aHasDirtyRegion; + } + + bool MayHaveWillChangeBudget() const { return mMayHaveWillChangeBudget; } + void SetMayHaveWillChangeBudget(const bool aHasBudget) { + mMayHaveWillChangeBudget = aHasBudget; + } + + bool HasBSizeChange() const { return mHasBSizeChange; } + void SetHasBSizeChange(const bool aHasBSizeChange) { + mHasBSizeChange = aHasBSizeChange; + } + + bool HasPaddingChange() const { return mHasPaddingChange; } + void SetHasPaddingChange(const bool aHasPaddingChange) { + mHasPaddingChange = aHasPaddingChange; + } + + bool HasColumnSpanSiblings() const { return mHasColumnSpanSiblings; } + void SetHasColumnSpanSiblings(bool aHasColumnSpanSiblings) { + mHasColumnSpanSiblings = aHasColumnSpanSiblings; + } + + bool DescendantMayDependOnItsStaticPosition() const { + return mDescendantMayDependOnItsStaticPosition; + } + void SetDescendantMayDependOnItsStaticPosition(bool aValue) { + mDescendantMayDependOnItsStaticPosition = aValue; + } + + bool ShouldGenerateComputedInfo() const { + return mShouldGenerateComputedInfo; + } + void SetShouldGenerateComputedInfo(bool aValue) { + mShouldGenerateComputedInfo = aValue; + } + + /** + * Returns the hit test area of the frame. + */ + nsRect GetCompositorHitTestArea(nsDisplayListBuilder* aBuilder); + + /** + * Returns the set of flags indicating the properties of the frame that the + * compositor might care about for hit-testing purposes. Note that this + * function must be called during Gecko display list construction time (i.e + * while the frame tree is being traversed) because that is when the display + * list builder has the necessary state set up correctly. + */ + mozilla::gfx::CompositorHitTestInfo GetCompositorHitTestInfo( + nsDisplayListBuilder* aBuilder); + + /** + * Copies aWM to mWritingMode on 'this' and all its ancestors. + */ + inline void PropagateWritingModeToSelfAndAncestors(mozilla::WritingMode aWM); + + /** + * Observes or unobserves the element with an internal ResizeObserver, + * depending on whether it needs to update its last remembered size. + * Also removes a previously stored last remembered size if the element + * can no longer have it. + * @see {@link https://drafts.csswg.org/css-sizing-4/#last-remembered} + */ + void HandleLastRememberedSize(); + + protected: + /** + * Reparent this frame's view if it has one. + */ + void ReparentFrameViewTo(nsViewManager* aViewManager, nsView* aNewParentView); + + // Members + nsRect mRect; + nsCOMPtr<nsIContent> mContent; + RefPtr<ComputedStyle> mComputedStyle; + + private: + nsPresContext* const mPresContext; + nsContainerFrame* mParent; + nsIFrame* mNextSibling; // doubly-linked list of frames + nsIFrame* mPrevSibling; // Do not touch outside SetNextSibling! + + DisplayItemArray mDisplayItems; + + void MarkAbsoluteFramesForDisplayList(nsDisplayListBuilder* aBuilder); + + protected: + void MarkInReflow() { +#ifdef DEBUG_dbaron_off + // bug 81268 + NS_ASSERTION(!(mState & NS_FRAME_IN_REFLOW), "frame is already in reflow"); +#endif + AddStateBits(NS_FRAME_IN_REFLOW); + } + + private: + nsFrameState mState; + + protected: + /** + * List of properties attached to the frame. + */ + FrameProperties mProperties; + + // When there is no scrollable overflow area, and the ink overflow area only + // slightly larger than mRect, the ink overflow area may be stored a set of + // four 1-byte deltas from the edges of mRect rather than allocating a whole + // separate rectangle property. If all four deltas are zero, this means that + // no overflow area has actually been set (this is the initial state of + // newly-created frames). + // + // Note that these are unsigned values, all measured "outwards" from the edges + // of mRect, so mLeft and mTop are reversed from our normal coordinate system. + struct InkOverflowDeltas { + // The maximum delta value we can store in any of the four edges. + static constexpr uint8_t kMax = 0xfe; + + uint8_t mLeft; + uint8_t mTop; + uint8_t mRight; + uint8_t mBottom; + bool operator==(const InkOverflowDeltas& aOther) const { + return mLeft == aOther.mLeft && mTop == aOther.mTop && + mRight == aOther.mRight && mBottom == aOther.mBottom; + } + bool operator!=(const InkOverflowDeltas& aOther) const { + return !(*this == aOther); + } + }; + enum class OverflowStorageType : uint32_t { + // No overflow area; code relies on this being an all-zero value. + None = 0x00000000u, + + // Ink overflow is too large to stored in InkOverflowDeltas. + Large = 0x000000ffu, + }; + // If mOverflow.mType is OverflowStorageType::Large, then the delta values are + // not meaningful and the overflow area is stored in OverflowAreasProperty() + // instead. + union { + OverflowStorageType mType; + InkOverflowDeltas mInkOverflowDeltas; + } mOverflow; + + /** @see GetWritingMode() */ + mozilla::WritingMode mWritingMode; + + /** The ClassID of the concrete class of this instance. */ + ClassID mClass; // 1 byte + + bool mMayHaveRoundedCorners : 1; + + /** + * True iff this frame has one or more associated image requests. + * @see mozilla::css::ImageLoader. + */ + bool mHasImageRequest : 1; + + /** + * True if this frame has a continuation that has a first-letter frame, or its + * placeholder, as a child. In that case this frame has a blockframe ancestor + * that has the first-letter frame hanging off it in the + * nsContainerFrame::FirstLetterProperty() property. + */ + bool mHasFirstLetterChild : 1; + + /** + * True if this frame's parent is a wrapper anonymous box (e.g. a table + * anonymous box as specified at + * <https://www.w3.org/TR/CSS21/tables.html#anonymous-boxes>). + * + * We could compute this information directly when we need it, but it wouldn't + * be all that cheap, and since this information is immutable for the lifetime + * of the frame we might as well cache it. + * + * Note that our parent may itself have mParentIsWrapperAnonBox set to true. + */ + bool mParentIsWrapperAnonBox : 1; + + /** + * True if this is a wrapper anonymous box needing a restyle. This is used to + * track, during stylo post-traversal, whether we've already recomputed the + * style of this anonymous box, if we end up seeing it twice. + */ + bool mIsWrapperBoxNeedingRestyle : 1; + + /** + * This bit is used in nsTextFrame::CharacterDataChanged() as an optimization + * to skip redundant reflow-requests when the character data changes multiple + * times between reflows. If this flag is set, then it implies that the + * NS_FRAME_IS_DIRTY state bit is also set (and that intrinsic sizes have + * been marked as dirty on our ancestor chain). + * + * XXXdholbert This bit is *only* used on nsTextFrame, but it lives here on + * nsIFrame simply because this is where we've got unused state bits + * available in a gap. If bits become more scarce, we should perhaps consider + * expanding the range of frame-specific state bits in nsFrameStateBits.h and + * moving this to be one of those (e.g. by swapping one of the adjacent + * general-purpose bits to take the place of this bool:1 here, so we can grow + * that range of frame-specific bits by 1). + */ + bool mReflowRequestedForCharDataChange : 1; + + /** + * This bit is used during BuildDisplayList to mark frames that need to + * have display items rebuilt. We will descend into them if they are + * currently visible, even if they don't intersect the dirty area. + */ + bool mForceDescendIntoIfVisible : 1; + + /** + * True if we have built display items for this frame since + * the last call to CheckAndClearDisplayListState, false + * otherwise. Used for the reftest harness to verify minimal + * display list building. + */ + bool mBuiltDisplayList : 1; + + /** + * True if the frame has been marked modified by + * |MarkNeedsDisplayItemRebuild()|, usually due to a style change or reflow. + */ + bool mFrameIsModified : 1; + + /** + * True if the frame has modified descendants. Set before display list + * preprocessing and only used during partial display list builds. + */ + bool mHasModifiedDescendants : 1; + + /** + * Used by merging based retained display lists to restrict the dirty area + * during partial display list builds. + */ + bool mHasOverrideDirtyRegion : 1; + + /** + * True if frame has will-change, and currently has display + * items consuming some of the will-change budget. + */ + bool mMayHaveWillChangeBudget : 1; + +#ifdef DEBUG + public: + /** + * True if this frame has already been been visited by + * nsCSSFrameConstructor::AutoFrameConstructionPageName. + * + * This is used to assert that we have visited each frame only once, and is + * not useful otherwise. + */ + bool mWasVisitedByAutoFrameConstructionPageName : 1; +#endif + + private: + /** + * True if this is the primary frame for mContent. + */ + bool mIsPrimaryFrame : 1; + + bool mMayHaveTransformAnimation : 1; + bool mMayHaveOpacityAnimation : 1; + + /** + * True if we are certain that all descendants are not visible. + * + * This flag is conservative in that it might sometimes be false even if, in + * fact, all descendants are invisible. + * For example; an element is visibility:visible and has a visibility:hidden + * child. This flag is stil false in such case. + */ + bool mAllDescendantsAreInvisible : 1; + + bool mHasBSizeChange : 1; + + /** + * True if the frame seems to be in the process of being reflowed with a + * different amount of inline-axis padding as compared to its most recent + * reflow. This flag's purpose is to detect cases where the frame's + * inline-axis content-box-size has changed, without any style change or any + * change to the border-box size, so that we can mark/invalidate things + * appropriately in ReflowInput::InitResizeFlags(). + * + * This flag is set in SizeComputationResult::InitOffsets() and cleared in + * nsIFrame::DidReflow(). + */ + bool mHasPaddingChange : 1; + + /** + * True if we are or contain the scroll anchor for a scrollable frame. + */ + bool mInScrollAnchorChain : 1; + + /** + * Suppose a frame was split into multiple parts to separate parts containing + * column-spans from parts not containing column-spans. This bit is set on all + * continuations *not* containing column-spans except for the those after the + * last column-span/non-column-span boundary (i.e., the bit really means it + * has a *later* sibling across a split). Note that the last part is always + * created to containing no columns-spans even if it has no children. See + * nsCSSFrameConstructor::CreateColumnSpanSiblings() for the implementation. + * + * If the frame having this bit set is removed, we need to reframe the + * multi-column container. + */ + bool mHasColumnSpanSiblings : 1; + + /** + * True if we may have any descendant whose positioning may depend on its + * static position (and thus which we need to recompute the position for if we + * move). + */ + bool mDescendantMayDependOnItsStaticPosition : 1; + + /** + * True if the next reflow of this frame should generate computed info + * metrics. These are used by devtools to reveal details of the layout + * process. + */ + bool mShouldGenerateComputedInfo : 1; + + protected: + // Helpers + /** + * Can we stop inside this frame when we're skipping non-rendered whitespace? + * + * @param aForward [in] Are we moving forward (or backward) in content order. + * + * @param aOffset [in/out] At what offset into the frame to start looking. + * at offset was reached (whether or not we found a place to stop). + * + * @return + * * STOP: An appropriate offset was found within this frame, + * and is given by aOffset. + * * CONTINUE: Not found within this frame, need to try the next frame. + * See enum FrameSearchResult for more details. + */ + virtual FrameSearchResult PeekOffsetNoAmount(bool aForward, int32_t* aOffset); + + /** + * Search the frame for the next character + * + * @param aForward [in] Are we moving forward (or backward) in content order. + * + * @param aOffset [in/out] At what offset into the frame to start looking. + * on output - what offset was reached (whether or not we found a place to + * stop). + * + * @param aOptions [in] Options, see the comment in PeekOffsetCharacterOptions + * for the detail. + * + * @return + * * STOP: An appropriate offset was found within this frame, and is given + * by aOffset. + * * CONTINUE: Not found within this frame, need to try the next frame. See + * enum FrameSearchResult for more details. + */ + virtual FrameSearchResult PeekOffsetCharacter( + bool aForward, int32_t* aOffset, + PeekOffsetCharacterOptions aOptions = PeekOffsetCharacterOptions()); + static_assert(sizeof(PeekOffsetCharacterOptions) <= sizeof(intptr_t), + "aOptions should be changed to const reference"); + + struct PeekWordState { + // true when we're still at the start of the search, i.e., we can't return + // this point as a valid offset! + bool mAtStart; + // true when we've encountered at least one character of the type before the + // boundary we're looking for: + // 1. If we're moving forward and eating whitepace, looking for a word + // beginning (i.e. a boundary between whitespace and non-whitespace), + // then mSawBeforeType==true means "we already saw some whitespace". + // 2. Otherwise, looking for a word beginning (i.e. a boundary between + // non-whitespace and whitespace), then mSawBeforeType==true means "we + // already saw some non-whitespace". + bool mSawBeforeType; + // true when we've encountered at least one non-newline character + bool mSawInlineCharacter; + // true when the last character encountered was punctuation + bool mLastCharWasPunctuation; + // true when the last character encountered was whitespace + bool mLastCharWasWhitespace; + // true when we've seen non-punctuation since the last whitespace + bool mSeenNonPunctuationSinceWhitespace; + // text that's *before* the current frame when aForward is true, *after* + // the current frame when aForward is false. Only includes the text + // on the current line. + nsAutoString mContext; + + PeekWordState() + : mAtStart(true), + mSawBeforeType(false), + mSawInlineCharacter(false), + mLastCharWasPunctuation(false), + mLastCharWasWhitespace(false), + mSeenNonPunctuationSinceWhitespace(false) {} + void SetSawBeforeType() { mSawBeforeType = true; } + void SetSawInlineCharacter() { mSawInlineCharacter = true; } + void Update(bool aAfterPunctuation, bool aAfterWhitespace) { + mLastCharWasPunctuation = aAfterPunctuation; + mLastCharWasWhitespace = aAfterWhitespace; + if (aAfterWhitespace) { + mSeenNonPunctuationSinceWhitespace = false; + } else if (!aAfterPunctuation) { + mSeenNonPunctuationSinceWhitespace = true; + } + mAtStart = false; + } + }; + + /** + * Search the frame for the next word boundary + * @param aForward [in] Are we moving forward (or backward) in content order. + * @param aWordSelectEatSpace [in] true: look for non-whitespace following + * whitespace (in the direction of movement). + * false: look for whitespace following non-whitespace (in the + * direction of movement). + * @param aIsKeyboardSelect [in] Was the action initiated by a keyboard + * operation? If true, punctuation immediately following a word is considered + * part of that word. Otherwise, a sequence of punctuation is always + * considered as a word on its own. + * @param aOffset [in/out] At what offset into the frame to start looking. + * on output - what offset was reached (whether or not we found a + * place to stop). + * @param aState [in/out] the state that is carried from frame to frame + */ + virtual FrameSearchResult PeekOffsetWord( + bool aForward, bool aWordSelectEatSpace, bool aIsKeyboardSelect, + int32_t* aOffset, PeekWordState* aState, bool aTrimSpaces); + + protected: + /** + * Check whether we should break at a boundary between punctuation and + * non-punctuation. Only call it at a punctuation boundary + * (i.e. exactly one of the previous and next characters are punctuation). + * @param aForward true if we're moving forward in content order + * @param aPunctAfter true if the next character is punctuation + * @param aWhitespaceAfter true if the next character is whitespace + */ + static bool BreakWordBetweenPunctuation(const PeekWordState* aState, + bool aForward, bool aPunctAfter, + bool aWhitespaceAfter, + bool aIsKeyboardSelect); + + private: + nsRect GetOverflowRect(mozilla::OverflowType aType) const; + + // Get a pointer to the overflow areas property attached to the frame. + mozilla::OverflowAreas* GetOverflowAreasProperty() const { + MOZ_ASSERT(mOverflow.mType == OverflowStorageType::Large); + mozilla::OverflowAreas* overflow = GetProperty(OverflowAreasProperty()); + MOZ_ASSERT(overflow); + return overflow; + } + + nsRect InkOverflowFromDeltas() const { + MOZ_ASSERT(mOverflow.mType != OverflowStorageType::Large, + "should not be called when overflow is in a property"); + // Calculate the rect using deltas from the frame's border rect. + // Note that the mOverflow.mInkOverflowDeltas fields are unsigned, but we + // will often need to return negative values for the left and top, so take + // care to cast away the unsigned-ness. + return nsRect(-(int32_t)mOverflow.mInkOverflowDeltas.mLeft, + -(int32_t)mOverflow.mInkOverflowDeltas.mTop, + mRect.Width() + mOverflow.mInkOverflowDeltas.mRight + + mOverflow.mInkOverflowDeltas.mLeft, + mRect.Height() + mOverflow.mInkOverflowDeltas.mBottom + + mOverflow.mInkOverflowDeltas.mTop); + } + + /** + * Set the OverflowArea rect, storing it as deltas or a separate rect + * depending on its size in relation to the primary frame rect. + * + * @return true if any overflow changed. + */ + bool SetOverflowAreas(const mozilla::OverflowAreas& aOverflowAreas); + + bool HasOpacityInternal(float aThreshold, const nsStyleDisplay* aStyleDisplay, + const nsStyleEffects* aStyleEffects, + mozilla::EffectSet* aEffectSet = nullptr) const; + + // Maps mClass to LayoutFrameType. + static const mozilla::LayoutFrameType sLayoutFrameTypes[ +#define FRAME_ID(...) 1 + +#define ABSTRACT_FRAME_ID(...) +#include "mozilla/FrameIdList.h" +#undef FRAME_ID +#undef ABSTRACT_FRAME_ID + 0]; + + enum FrameClassBits { + eFrameClassBitsNone = 0x0, + eFrameClassBitsLeaf = 0x1, + eFrameClassBitsDynamicLeaf = 0x2, + }; + // Maps mClass to IsLeaf() flags. + static const FrameClassBits sFrameClassBits[ +#define FRAME_ID(...) 1 + +#define ABSTRACT_FRAME_ID(...) +#include "mozilla/FrameIdList.h" +#undef FRAME_ID +#undef ABSTRACT_FRAME_ID + 0]; + +#ifdef DEBUG_FRAME_DUMP + public: + static void IndentBy(FILE* out, int32_t aIndent) { + while (--aIndent >= 0) fputs(" ", out); + } + void ListTag(FILE* out) const { fputs(ListTag().get(), out); } + nsAutoCString ListTag() const; + + enum class ListFlag{TraverseSubdocumentFrames, DisplayInCSSPixels}; + using ListFlags = mozilla::EnumSet<ListFlag>; + + template <typename T> + static std::string ConvertToString(const T& aValue, ListFlags aFlags) { + // This method can convert all physical types in app units to CSS pixels. + return aFlags.contains(ListFlag::DisplayInCSSPixels) + ? mozilla::ToString(mozilla::CSSPixel::FromAppUnits(aValue)) + : mozilla::ToString(aValue); + } + static std::string ConvertToString(const mozilla::LogicalRect& aRect, + const mozilla::WritingMode aWM, + ListFlags aFlags); + static std::string ConvertToString(const mozilla::LogicalSize& aSize, + const mozilla::WritingMode aWM, + ListFlags aFlags); + + void ListGeneric(nsACString& aTo, const char* aPrefix = "", + ListFlags aFlags = ListFlags()) const; + virtual void List(FILE* out = stderr, const char* aPrefix = "", + ListFlags aFlags = ListFlags()) const; + + void ListTextRuns(FILE* out = stderr) const; + virtual void ListTextRuns(FILE* out, nsTHashSet<const void*>& aSeen) const; + + virtual void ListWithMatchedRules(FILE* out = stderr, + const char* aPrefix = "") const; + void ListMatchedRules(FILE* out, const char* aPrefix) const; + + /** + * Dump the frame tree beginning from the root frame. + */ + void DumpFrameTree() const; + void DumpFrameTreeInCSSPixels() const; + + /** + * Dump the frame tree beginning from ourselves. + */ + void DumpFrameTreeLimited() const; + void DumpFrameTreeLimitedInCSSPixels() const; + + /** + * Get a printable from of the name of the frame type. + * XXX This should be eliminated and we use GetType() instead... + */ + virtual nsresult GetFrameName(nsAString& aResult) const; + nsresult MakeFrameName(const nsAString& aType, nsAString& aResult) const; + // Helper function to return the index in parent of the frame's content + // object. Returns Nothing on error or if the frame doesn't have a content + // object + static mozilla::Maybe<uint32_t> ContentIndexInContainer( + const nsIFrame* aFrame); +#endif + +#ifdef DEBUG + /** + * Tracing method that writes a method enter/exit routine to the + * nspr log using the nsIFrame log module. The tracing is only + * done when the NS_FRAME_TRACE_CALLS bit is set in the log module's + * level field. + */ + void Trace(const char* aMethod, bool aEnter); + void Trace(const char* aMethod, bool aEnter, const nsReflowStatus& aStatus); + void TraceMsg(const char* aFormatString, ...) MOZ_FORMAT_PRINTF(2, 3); + + // Helper function that verifies that each frame in the list has the + // NS_FRAME_IS_DIRTY bit set + static void VerifyDirtyBitSet(const nsFrameList& aFrameList); + + // Display Reflow Debugging + static void* DisplayReflowEnter(nsPresContext* aPresContext, nsIFrame* aFrame, + const ReflowInput& aReflowInput); + static void* DisplayLayoutEnter(nsIFrame* aFrame); + static void* DisplayIntrinsicISizeEnter(nsIFrame* aFrame, const char* aType); + static void* DisplayIntrinsicSizeEnter(nsIFrame* aFrame, const char* aType); + static void DisplayReflowExit(nsPresContext* aPresContext, nsIFrame* aFrame, + ReflowOutput& aMetrics, + const nsReflowStatus& aStatus, + void* aFrameTreeNode); + static void DisplayLayoutExit(nsIFrame* aFrame, void* aFrameTreeNode); + static void DisplayIntrinsicISizeExit(nsIFrame* aFrame, const char* aType, + nscoord aResult, void* aFrameTreeNode); + static void DisplayIntrinsicSizeExit(nsIFrame* aFrame, const char* aType, + nsSize aResult, void* aFrameTreeNode); + + static void DisplayReflowStartup(); + static void DisplayReflowShutdown(); + + static mozilla::LazyLogModule sFrameLogModule; +#endif +}; + +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(nsIFrame::ReflowChildFlags) + +//---------------------------------------------------------------------- + +/** + * AutoWeakFrame can be used to keep a reference to a nsIFrame in a safe way. + * Whenever an nsIFrame object is deleted, the AutoWeakFrames pointing + * to it will be cleared. AutoWeakFrame is for variables on the stack or + * in static storage only, there is also a WeakFrame below for heap uses. + * + * Create AutoWeakFrame object when it is sure that nsIFrame object + * is alive and after some operations which may destroy the nsIFrame + * (for example any DOM modifications) use IsAlive() or GetFrame() methods to + * check whether it is safe to continue to use the nsIFrame object. + * + * @note The usage of this class should be kept to a minimum. + */ +class WeakFrame; +class MOZ_NONHEAP_CLASS AutoWeakFrame { + public: + explicit AutoWeakFrame() : mPrev(nullptr), mFrame(nullptr) {} + + AutoWeakFrame(const AutoWeakFrame& aOther) : mPrev(nullptr), mFrame(nullptr) { + Init(aOther.GetFrame()); + } + + MOZ_IMPLICIT AutoWeakFrame(const WeakFrame& aOther); + + MOZ_IMPLICIT AutoWeakFrame(nsIFrame* aFrame) + : mPrev(nullptr), mFrame(nullptr) { + Init(aFrame); + } + + AutoWeakFrame& operator=(AutoWeakFrame& aOther) { + Init(aOther.GetFrame()); + return *this; + } + + AutoWeakFrame& operator=(nsIFrame* aFrame) { + Init(aFrame); + return *this; + } + + nsIFrame* operator->() { return mFrame; } + + operator nsIFrame*() { return mFrame; } + + void Clear(mozilla::PresShell* aPresShell); + + bool IsAlive() const { return !!mFrame; } + + nsIFrame* GetFrame() const { return mFrame; } + + AutoWeakFrame* GetPreviousWeakFrame() { return mPrev; } + + void SetPreviousWeakFrame(AutoWeakFrame* aPrev) { mPrev = aPrev; } + + ~AutoWeakFrame(); + + private: + // Not available for the heap! + void* operator new(size_t) = delete; + void* operator new[](size_t) = delete; + void operator delete(void*) = delete; + void operator delete[](void*) = delete; + + void Init(nsIFrame* aFrame); + + AutoWeakFrame* mPrev; + nsIFrame* mFrame; +}; + +// Use nsIFrame's fast-path to avoid QueryFrame: +inline do_QueryFrameHelper<nsIFrame> do_QueryFrame(AutoWeakFrame& s) { + return do_QueryFrameHelper<nsIFrame>(s.GetFrame()); +} + +/** + * @see AutoWeakFrame + */ +class MOZ_HEAP_CLASS WeakFrame { + public: + WeakFrame() : mFrame(nullptr) {} + + WeakFrame(const WeakFrame& aOther) : mFrame(nullptr) { + Init(aOther.GetFrame()); + } + + MOZ_IMPLICIT WeakFrame(const AutoWeakFrame& aOther) : mFrame(nullptr) { + Init(aOther.GetFrame()); + } + + MOZ_IMPLICIT WeakFrame(nsIFrame* aFrame) : mFrame(nullptr) { Init(aFrame); } + + ~WeakFrame() { + Clear(mFrame ? mFrame->PresContext()->GetPresShell() : nullptr); + } + + WeakFrame& operator=(WeakFrame& aOther) { + Init(aOther.GetFrame()); + return *this; + } + + WeakFrame& operator=(nsIFrame* aFrame) { + Init(aFrame); + return *this; + } + + nsIFrame* operator->() { return mFrame; } + operator nsIFrame*() { return mFrame; } + + void Clear(mozilla::PresShell* aPresShell); + + bool IsAlive() const { return !!mFrame; } + nsIFrame* GetFrame() const { return mFrame; } + + private: + void Init(nsIFrame* aFrame); + + nsIFrame* mFrame; +}; + +// Use nsIFrame's fast-path to avoid QueryFrame: +inline do_QueryFrameHelper<nsIFrame> do_QueryFrame(WeakFrame& s) { + return do_QueryFrameHelper<nsIFrame>(s.GetFrame()); +} + +inline bool nsFrameList::ContinueRemoveFrame(nsIFrame* aFrame) { + MOZ_ASSERT(!aFrame->GetPrevSibling() || !aFrame->GetNextSibling(), + "Forgot to call StartRemoveFrame?"); + if (aFrame == mLastChild) { + MOZ_ASSERT(!aFrame->GetNextSibling(), "broken frame list"); + nsIFrame* prevSibling = aFrame->GetPrevSibling(); + if (!prevSibling) { + MOZ_ASSERT(aFrame == mFirstChild, "broken frame list"); + mFirstChild = mLastChild = nullptr; + return true; + } + MOZ_ASSERT(prevSibling->GetNextSibling() == aFrame, "Broken frame linkage"); + prevSibling->SetNextSibling(nullptr); + mLastChild = prevSibling; + return true; + } + if (aFrame == mFirstChild) { + MOZ_ASSERT(!aFrame->GetPrevSibling(), "broken frame list"); + mFirstChild = aFrame->GetNextSibling(); + aFrame->SetNextSibling(nullptr); + MOZ_ASSERT(mFirstChild, "broken frame list"); + return true; + } + return false; +} + +inline bool nsFrameList::StartRemoveFrame(nsIFrame* aFrame) { + if (aFrame->GetPrevSibling() && aFrame->GetNextSibling()) { + UnhookFrameFromSiblings(aFrame); + return true; + } + return ContinueRemoveFrame(aFrame); +} + +// Operators of nsFrameList::Iterator +// --------------------------------------------------- + +inline nsIFrame* nsFrameList::ForwardFrameTraversal::Next(nsIFrame* aFrame) { + MOZ_ASSERT(aFrame); + return aFrame->GetNextSibling(); +} +inline nsIFrame* nsFrameList::ForwardFrameTraversal::Prev(nsIFrame* aFrame) { + MOZ_ASSERT(aFrame); + return aFrame->GetPrevSibling(); +} + +inline nsIFrame* nsFrameList::BackwardFrameTraversal::Next(nsIFrame* aFrame) { + MOZ_ASSERT(aFrame); + return aFrame->GetPrevSibling(); +} +inline nsIFrame* nsFrameList::BackwardFrameTraversal::Prev(nsIFrame* aFrame) { + MOZ_ASSERT(aFrame); + return aFrame->GetNextSibling(); +} + +#endif /* nsIFrame_h___ */ |